diff --git a/app/src/main/java/org/schabi/newpipe/download/DownloadDialog.java b/app/src/main/java/org/schabi/newpipe/download/DownloadDialog.java
index 0418eadae..4f98f7f28 100644
--- a/app/src/main/java/org/schabi/newpipe/download/DownloadDialog.java
+++ b/app/src/main/java/org/schabi/newpipe/download/DownloadDialog.java
@@ -416,7 +416,8 @@ public class DownloadDialog extends DialogFragment implements RadioGroup.OnCheck
         // fallback
         // 1st loop match country & language
         // 2nd loop match language only
-        String lang = loc.getLanguage().substring(0, loc.getLanguage().indexOf("-"));
+        int index = loc.getLanguage().indexOf("-");
+        String lang = index > 0 ? loc.getLanguage().substring(0, index) : loc.getLanguage();
 
         for (int j = 0; j < 2; j++) {
             for (int i = 0; i < streams.size(); i++) {
diff --git a/app/src/main/java/us/shandian/giga/get/DownloadMission.java b/app/src/main/java/us/shandian/giga/get/DownloadMission.java
index 851b5cb1b..79e01b8cc 100644
--- a/app/src/main/java/us/shandian/giga/get/DownloadMission.java
+++ b/app/src/main/java/us/shandian/giga/get/DownloadMission.java
@@ -221,12 +221,12 @@ public class DownloadMission extends Mission {
     }
 
     /**
-     * Get position inside of the block, where thread will be resumed
+     * Get position inside of the thread, where thread will be resumed
      *
      * @param threadId the identifier of the thread
      * @return the relative position in bytes or zero
      */
-    long getBlockBytePosition(int threadId) {
+    long getThreadBytePosition(int threadId) {
         return threadBytePositions.get(threadId);
     }
 
@@ -256,6 +256,8 @@ public class DownloadMission extends Mission {
             }
         }
 
+        conn.connect();
+
         int statusCode = conn.getResponseCode();
         switch (statusCode) {
             case 204:
@@ -446,6 +448,8 @@ public class DownloadMission extends Mission {
             return;
         }
 
+        if (postprocessingRunning) return;
+
         // wait for all threads are suspended before save the state
         runAsync(-1, () -> {
             try {
@@ -590,7 +594,7 @@ public class DownloadMission extends Mission {
 
         @Override
         public String getMessage() {
-            return "Http status code" + String.valueOf(statusCode);
+            return "Http status code: " + String.valueOf(statusCode);
         }
     }
 }
diff --git a/app/src/main/java/us/shandian/giga/get/DownloadRunnable.java b/app/src/main/java/us/shandian/giga/get/DownloadRunnable.java
index 95f4758f9..336bc13ee 100644
--- a/app/src/main/java/us/shandian/giga/get/DownloadRunnable.java
+++ b/app/src/main/java/us/shandian/giga/get/DownloadRunnable.java
@@ -2,11 +2,10 @@ package us.shandian.giga.get;
 
 import android.util.Log;
 
-import java.io.BufferedInputStream;
 import java.io.FileNotFoundException;
+import java.io.InputStream;
 import java.io.RandomAccessFile;
 import java.net.HttpURLConnection;
-import java.net.URL;
 import java.nio.channels.ClosedByInterruptException;
 
 import static org.schabi.newpipe.BuildConfig.DEBUG;
@@ -38,8 +37,8 @@ public class DownloadRunnable implements Runnable {
             Log.d(TAG, mId + ":recovered: " + mMission.recovered);
         }
 
-        BufferedInputStream ipt = null;
         RandomAccessFile f;
+        InputStream is = null;
 
         try {
             f = new RandomAccessFile(mMission.getDownloadedFile(), "rw");
@@ -82,9 +81,11 @@ public class DownloadRunnable implements Runnable {
             mMission.preserveBlock(blockPosition);
             mMission.setBlockPosition(mId, blockPosition);
 
-            long start = (blockPosition * DownloadMission.BLOCK_SIZE) + mMission.getBlockBytePosition(mId);
+            long start = blockPosition * DownloadMission.BLOCK_SIZE;
             long end = start + DownloadMission.BLOCK_SIZE - 1;
 
+            start += mMission.getThreadBytePosition(mId);
+
             if (end >= mMission.length) {
                 end = mMission.length - 1;
             }
@@ -107,11 +108,11 @@ public class DownloadRunnable implements Runnable {
 
                 f.seek(mMission.offsets[mMission.current] + start);
 
-                ipt = new BufferedInputStream(conn.getInputStream());
+                is = conn.getInputStream();
                 byte[] buf = new byte[DownloadMission.BUFFER_SIZE];
                 int len;
 
-                while (start < end && mMission.running && (len = ipt.read(buf, 0, buf.length)) != -1) {
+                while (start < end && mMission.running && (len = is.read(buf, 0, buf.length)) != -1) {
                     f.write(buf, 0, len);
                     start += len;
                     total += len;
@@ -119,7 +120,8 @@ public class DownloadRunnable implements Runnable {
                 }
 
                 if (DEBUG && mMission.running) {
-                    Log.d(TAG, mId + ":position " + blockPosition + " finished, total length " + total);
+                    Log.d(TAG, mId + ":position " + blockPosition + " finished, " + total + " bytes downloaded");
+                    mMission.setThreadBytePosition(mId, 0L);
                 }
 
                 // if the download is paused, save progress for this thread
@@ -132,7 +134,7 @@ public class DownloadRunnable implements Runnable {
 
                 if (e instanceof ClosedByInterruptException) break;
 
-                if (retryCount++ > mMission.maxRetry) {
+                if (retryCount++ >= mMission.maxRetry) {
                     mMission.notifyError(e);
                     break;
                 }
@@ -140,6 +142,8 @@ public class DownloadRunnable implements Runnable {
                 if (DEBUG) {
                     Log.d(TAG, mId + ":position " + blockPosition + " retrying due exception", e);
                 }
+
+                retry = true;
             }
         }
 
@@ -150,7 +154,7 @@ public class DownloadRunnable implements Runnable {
         }
 
         try {
-            if (ipt != null) ipt.close();
+            if (is != null) is.close();
         } catch (Exception err) {
             // nothing to do
         }
diff --git a/app/src/main/java/us/shandian/giga/get/DownloadRunnableFallback.java b/app/src/main/java/us/shandian/giga/get/DownloadRunnableFallback.java
index b648dd812..5ef4ed90e 100644
--- a/app/src/main/java/us/shandian/giga/get/DownloadRunnableFallback.java
+++ b/app/src/main/java/us/shandian/giga/get/DownloadRunnableFallback.java
@@ -4,8 +4,8 @@ import android.annotation.SuppressLint;
 import android.support.annotation.NonNull;
 import android.util.Log;
 
-import java.io.BufferedInputStream;
 import java.io.IOException;
+import java.io.InputStream;
 import java.io.RandomAccessFile;
 import java.net.HttpURLConnection;
 import java.nio.channels.ClosedByInterruptException;
@@ -24,18 +24,18 @@ public class DownloadRunnableFallback implements Runnable {
     private final DownloadMission mMission;
     private int retryCount = 0;
 
-    private BufferedInputStream ipt;
+    private InputStream is;
     private RandomAccessFile f;
 
     DownloadRunnableFallback(@NonNull DownloadMission mission) {
         mMission = mission;
-        ipt = null;
+        is = null;
         f = null;
     }
 
     private void dispose() {
         try {
-            if (ipt != null) ipt.close();
+            if (is != null) is.close();
         } catch (IOException e) {
             // nothing to do
         }
@@ -55,7 +55,7 @@ public class DownloadRunnableFallback implements Runnable {
         long start = 0;
 
         if (!mMission.unknownLength) {
-            start = mMission.getBlockBytePosition(0);
+            start = mMission.getThreadBytePosition(0);
             if (DEBUG && start > 0) {
                 Log.i(TAG, "Resuming a single-thread download at " + start);
             }
@@ -72,18 +72,15 @@ public class DownloadRunnableFallback implements Runnable {
             f = new RandomAccessFile(mMission.getDownloadedFile(), "rw");
             f.seek(mMission.offsets[mMission.current] + start);
 
-            ipt = new BufferedInputStream(conn.getInputStream());
+            is = conn.getInputStream();
 
-            byte[] buf = new byte[DownloadMission.BUFFER_SIZE];
+            byte[] buf = new byte[64 * 1024];
             int len = 0;
 
-            while (mMission.running && (len = ipt.read(buf, 0, buf.length)) != -1) {
+            while (mMission.running && (len = is.read(buf, 0, buf.length)) != -1) {
                 f.write(buf, 0, len);
                 start += len;
-
                 mMission.notifyProgress(len);
-
-                if (Thread.interrupted()) break;
             }
 
             // if thread goes interrupted check if the last part is written. This avoid re-download the whole file
@@ -96,7 +93,7 @@ public class DownloadRunnableFallback implements Runnable {
 
             if (e instanceof ClosedByInterruptException) return;
 
-            if (retryCount++ > mMission.maxRetry) {
+            if (retryCount++ >= mMission.maxRetry) {
                 mMission.notifyError(e);
                 return;
             }
diff --git a/app/src/main/java/us/shandian/giga/postprocessing/io/CircularFile.java b/app/src/main/java/us/shandian/giga/postprocessing/io/CircularFile.java
index 1454c1f2d..7e5ad9929 100644
--- a/app/src/main/java/us/shandian/giga/postprocessing/io/CircularFile.java
+++ b/app/src/main/java/us/shandian/giga/postprocessing/io/CircularFile.java
@@ -10,8 +10,10 @@ import java.util.ArrayList;
 public class CircularFile extends SharpStream {
 
     private final static int AUX_BUFFER_SIZE = 1024 * 1024;// 1 MiB
-    private final static int NOTIFY_BYTES_INTERVAL = 256 * 1024;// 256 KiB
+    private final static int AUX_BUFFER_SIZE2 = 512 * 1024;// 512 KiB
+    private final static int NOTIFY_BYTES_INTERVAL = 64 * 1024;// 64 KiB
     private final static int QUEUE_BUFFER_SIZE = 8 * 1024;// 8 KiB
+    private final static boolean IMMEDIATE_AUX_BUFFER_FLUSH = false;
 
     private RandomAccessFile out;
     private long position;
@@ -45,7 +47,7 @@ public class CircularFile extends SharpStream {
             throw err;
         }
 
-        auxiliaryBuffers = new ArrayList<>(1);
+        auxiliaryBuffers = new ArrayList<>(15);
         callback = checker;
         startOffset = offset;
         reportPosition = offset;
@@ -122,7 +124,7 @@ public class CircularFile extends SharpStream {
         while (available > 0 && auxiliaryBuffers.size() > 0) {
             ManagedBuffer aux = auxiliaryBuffers.get(0);
 
-            // check if there is enough space to dump the auxiliar buffer
+            // check if there is enough space to dump the auxiliary buffer
             if (available >= (aux.size + queue.size)) {
                 available -= aux.size;
                 writeQueue(aux.buffer, 0, aux.size);
@@ -131,26 +133,27 @@ public class CircularFile extends SharpStream {
                 continue;
             }
 
-            // try flush contents to avoid allocate another auxiliar buffer
-            if (aux.available() < len && available > queue.size) {
-                int size = Math.min(len, aux.available());
-                aux.write(b, off, size);
+            if (IMMEDIATE_AUX_BUFFER_FLUSH) {
+                // try flush contents to avoid allocate another auxiliary buffer
+                if (aux.available() < len && available > queue.size) {
+                    int size = Math.min(len, aux.available());
+                    aux.write(b, off, size);
 
-                off += size;
-                len -= size;
+                    off += size;
+                    len -= size;
 
-                size = Math.min(aux.size, (int) available - queue.size);
-                if (size < 1) {
-                    break;
+                    size = Math.min(aux.size, (int) available - queue.size);
+                    if (size < 1) {
+                        break;
+                    }
+
+                    writeQueue(aux.buffer, 0, size);
+                    aux.dereference(size);
+
+                    available -= size;
                 }
-
-                writeQueue(aux.buffer, 0, size);
-                aux.dereference(size);
-
-                available -= size;
+                break;
             }
-
-            break;
         }
 
         if (len < 1) {
@@ -174,7 +177,7 @@ public class CircularFile extends SharpStream {
                 if (available < 1) {
                     // secondary auxiliary buffer
                     available = len;
-                    aux = new ManagedBuffer(Math.max(len, AUX_BUFFER_SIZE));
+                    aux = new ManagedBuffer(Math.max(len, AUX_BUFFER_SIZE2));
                     auxiliaryBuffers.add(aux);
                     i++;
                 } else {
@@ -184,10 +187,7 @@ public class CircularFile extends SharpStream {
                 aux.write(b, off, (int) available);
 
                 len -= available;
-                if (len < 1) {
-                    break;
-                }
-                off += available;
+                if (len > 0) off += available;
             }
         }
     }
@@ -361,12 +361,8 @@ public class CircularFile extends SharpStream {
             if (amount > size) {
                 throw new IndexOutOfBoundsException("Invalid dereference amount (" + amount + ">=" + size + ")");
             }
-
             size -= amount;
-
-            for (int i = 0; i < size; i++) {
-                buffer[i] = buffer[amount + i];
-            }
+            System.arraycopy(buffer, amount, buffer, 0, size);
         }
 
         protected int available() {
diff --git a/app/src/main/java/us/shandian/giga/service/DownloadManager.java b/app/src/main/java/us/shandian/giga/service/DownloadManager.java
index 31b5b16a9..55a22c8c5 100644
--- a/app/src/main/java/us/shandian/giga/service/DownloadManager.java
+++ b/app/src/main/java/us/shandian/giga/service/DownloadManager.java
@@ -277,6 +277,7 @@ public class DownloadManager {
                 mDownloadDataSource.deleteMission(mission);
             }
 
+            mHandler.sendEmptyMessage(DownloadManagerService.MESSAGE_DELETED);
             mission.delete();
         }
     }
@@ -427,8 +428,8 @@ public class DownloadManager {
             if (!canDownloadInCurrentNetwork()) return false;
 
             for (DownloadMission mission : mMissionsPending) {
-                if (!mission.running && mission.errCode != DownloadMission.ERROR_POSTPROCESSING_FAILED && mission.enqueued) {
-                    resumeMission(mMissionsPending.get(i));
+                if (!mission.running && mission.errCode == DownloadMission.ERROR_NOTHING && mission.enqueued) {
+                    resumeMission(mission);
                     return true;
                 }
             }
diff --git a/app/src/main/java/us/shandian/giga/service/DownloadManagerService.java b/app/src/main/java/us/shandian/giga/service/DownloadManagerService.java
index 7b30740d5..7d88d9e2a 100755
--- a/app/src/main/java/us/shandian/giga/service/DownloadManagerService.java
+++ b/app/src/main/java/us/shandian/giga/service/DownloadManagerService.java
@@ -28,6 +28,7 @@ import android.support.v4.app.NotificationCompat;
 import android.support.v4.app.NotificationCompat.Builder;
 import android.support.v4.content.PermissionChecker;
 import android.util.Log;
+import android.util.SparseArray;
 import android.widget.Toast;
 
 import org.schabi.newpipe.R;
@@ -36,7 +37,6 @@ import org.schabi.newpipe.player.helper.LockManager;
 
 import java.io.File;
 import java.util.ArrayList;
-import java.util.Iterator;
 
 import us.shandian.giga.get.DownloadMission;
 import us.shandian.giga.service.DownloadManager.NetworkState;
@@ -46,13 +46,14 @@ import static org.schabi.newpipe.BuildConfig.DEBUG;
 
 public class DownloadManagerService extends Service {
 
-    private static final String TAG = DownloadManagerService.class.getSimpleName();
+    private static final String TAG = "DownloadManagerService";
 
-    public static final int MESSAGE_RUNNING = 1;
-    public static final int MESSAGE_PAUSED = 2;
-    public static final int MESSAGE_FINISHED = 3;
-    public static final int MESSAGE_PROGRESS = 4;
-    public static final int MESSAGE_ERROR = 5;
+    public static final int MESSAGE_RUNNING = 0;
+    public static final int MESSAGE_PAUSED = 1;
+    public static final int MESSAGE_FINISHED = 2;
+    public static final int MESSAGE_PROGRESS = 3;
+    public static final int MESSAGE_ERROR = 4;
+    public static final int MESSAGE_DELETED = 5;
 
     private static final int FOREGROUND_NOTIFICATION_ID = 1000;
     private static final int DOWNLOADS_NOTIFICATION_ID = 1001;
@@ -67,17 +68,20 @@ public class DownloadManagerService extends Service {
     private static final String EXTRA_SOURCE = "DownloadManagerService.extra.source";
     private static final String EXTRA_NEAR_LENGTH = "DownloadManagerService.extra.nearLength";
 
-    private static final String ACTION_RESET_DOWNLOAD_COUNT = APPLICATION_ID + ".reset_download_count";
+    private static final String ACTION_RESET_DOWNLOAD_FINISHED = APPLICATION_ID + ".reset_download_finished";
+    private static final String ACTION_OPEN_DOWNLOADS_FINISHED = APPLICATION_ID + ".open_downloads_finished";
 
     private DMBinder mBinder;
     private DownloadManager mManager;
     private Notification mNotification;
     private Handler mHandler;
+    private boolean mForeground = false;
+    private NotificationManager notificationManager = null;
+    private boolean mDownloadNotificationEnable = true;
+
     private int downloadDoneCount = 0;
     private Builder downloadDoneNotification = null;
     private StringBuilder downloadDoneList = null;
-    NotificationManager notificationManager = null;
-    private boolean mForeground = false;
 
     private final ArrayList<Handler> mEchoObservers = new ArrayList<>(1);
 
@@ -90,9 +94,14 @@ public class DownloadManagerService extends Service {
     private LockManager wakeLock = null;
 
     private int downloadFailedNotificationID = DOWNLOADS_NOTIFICATION_ID + 1;
+    private Builder downloadFailedNotification = null;
+    private SparseArray<DownloadMission> mFailedDownloads = new SparseArray<>(5);
 
     private Bitmap icLauncher;
     private Bitmap icDownloadDone;
+    private Bitmap icDownloadFailed;
+
+    private PendingIntent mOpenDownloadList;
 
     /**
      * notify media scanner on downloaded media file ...
@@ -124,14 +133,14 @@ public class DownloadManagerService extends Service {
         Intent openDownloadListIntent = new Intent(this, DownloadActivity.class)
                 .setAction(Intent.ACTION_MAIN);
 
-        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0,
+        mOpenDownloadList = PendingIntent.getActivity(this, 0,
                 openDownloadListIntent,
                 PendingIntent.FLAG_UPDATE_CURRENT);
 
         icLauncher = BitmapFactory.decodeResource(this.getResources(), R.mipmap.ic_launcher);
 
         Builder builder = new Builder(this, getString(R.string.notification_channel_id))
-                .setContentIntent(pendingIntent)
+                .setContentIntent(mOpenDownloadList)
                 .setSmallIcon(android.R.drawable.stat_sys_download)
                 .setLargeIcon(icLauncher)
                 .setContentTitle(getString(R.string.msg_running))
@@ -155,6 +164,9 @@ public class DownloadManagerService extends Service {
         mPrefs = PreferenceManager.getDefaultSharedPreferences(this);
         mPrefs.registerOnSharedPreferenceChangeListener(mPrefChangeListener);
 
+        handlePreferenceChange(mPrefs, getString(R.string.downloads_cross_network));
+        handlePreferenceChange(mPrefs, getString(R.string.downloads_max_retry));
+
         wakeLock = new LockManager(this);
     }
 
@@ -183,9 +195,17 @@ public class DownloadManagerService extends Service {
 
                 mHandler.post(() -> mManager.startMission(urls, location, name, kind, threads, source, psName, psArgs, nearLength));
 
-            } else if (downloadDoneNotification != null && action.equals(ACTION_RESET_DOWNLOAD_COUNT)) {
-                downloadDoneCount = 0;
-                downloadDoneList.setLength(0);
+            } else if (downloadDoneNotification != null) {
+                if (action.equals(ACTION_RESET_DOWNLOAD_FINISHED) || action.equals(ACTION_OPEN_DOWNLOADS_FINISHED)) {
+                    downloadDoneCount = 0;
+                    downloadDoneList.setLength(0);
+                }
+                if (action.equals(ACTION_OPEN_DOWNLOADS_FINISHED)) {
+                    startActivity(new Intent(this, DownloadActivity.class)
+                            .setAction(Intent.ACTION_MAIN)
+                            .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
+                    );
+                }
             }
         }
         return START_NOT_STICKY;
@@ -213,7 +233,8 @@ public class DownloadManagerService extends Service {
         unregisterReceiver(mNetworkStateListener);
         mPrefs.unregisterOnSharedPreferenceChangeListener(mPrefChangeListener);
 
-        icDownloadDone.recycle();
+        if (icDownloadDone != null) icDownloadDone.recycle();
+        if (icDownloadFailed != null) icDownloadFailed.recycle();
         icLauncher.recycle();
     }
 
@@ -250,7 +271,7 @@ public class DownloadManagerService extends Service {
                 updateForegroundState(true);
                 break;
             case MESSAGE_ERROR:
-                notifyFailedDownload(mission.name);
+                notifyFailedDownload(mission);
                 updateForegroundState(mManager.runAnotherMission());
                 break;
             case MESSAGE_PAUSED:
@@ -258,19 +279,16 @@ public class DownloadManagerService extends Service {
                 break;
         }
 
+        if (msg.what != MESSAGE_ERROR)
+            mFailedDownloads.delete(mFailedDownloads.indexOfValue(mission));
 
         synchronized (mEchoObservers) {
-            Iterator<Handler> iterator = mEchoObservers.iterator();
-            while (iterator.hasNext()) {
-                Handler handler = iterator.next();
-                if (handler.getLooper().getThread().isAlive()) {
-                    Message echo = new Message();
-                    echo.what = msg.what;
-                    echo.obj = msg.obj;
-                    handler.sendMessage(echo);
-                } else {
-                    iterator.remove();// ¿missing call to removeMissionEventListener()?
-                }
+            for (Handler handler : mEchoObservers) {
+                Message echo = new Message();
+                echo.what = msg.what;
+                echo.obj = msg.obj;
+
+                handler.sendMessage(echo);
             }
         }
     }
@@ -306,11 +324,14 @@ public class DownloadManagerService extends Service {
 
     private void handlePreferenceChange(SharedPreferences prefs, String key) {
         if (key.equals(getString(R.string.downloads_max_retry))) {
-            mManager.mPrefMaxRetry = Integer.parseInt(
-                    prefs.getString(key, getString(R.string.default_max_retry))
-            );
+            try {
+                String value = prefs.getString(key, getString(R.string.downloads_max_retry_default));
+                mManager.mPrefMaxRetry = Integer.parseInt(value);
+            } catch (Exception e) {
+                mManager.mPrefMaxRetry = 0;
+            }
             mManager.updateMaximumAttempts();
-        } else if (key.equals(getString(R.string.cross_network_downloads))) {
+        } else if (key.equals(getString(R.string.downloads_cross_network))) {
             mManager.mPrefCrossNetwork = prefs.getBoolean(key, false);
         }
     }
@@ -368,7 +389,7 @@ public class DownloadManagerService extends Service {
     }
 
     public void notifyFinishedDownload(String name) {
-        if (notificationManager == null) {
+        if (!mDownloadNotificationEnable || notificationManager == null) {
             return;
         }
 
@@ -380,14 +401,8 @@ public class DownloadManagerService extends Service {
                     .setAutoCancel(true)
                     .setLargeIcon(icDownloadDone)
                     .setSmallIcon(android.R.drawable.stat_sys_download_done)
-                    .setDeleteIntent(PendingIntent.getService(this, (int) System.currentTimeMillis(),
-                            new Intent(this, DownloadManagerService.class)
-                                    .setAction(ACTION_RESET_DOWNLOAD_COUNT)
-                            , PendingIntent.FLAG_UPDATE_CURRENT))
-                    .setContentIntent(PendingIntent.getService(this, (int) System.currentTimeMillis() + 1,
-                            new Intent(this, DownloadActivity.class)
-                                    .setAction(Intent.ACTION_MAIN),
-                            PendingIntent.FLAG_UPDATE_CURRENT));
+                    .setDeleteIntent(makePendingIntent(ACTION_RESET_DOWNLOAD_FINISHED))
+                    .setContentIntent(makePendingIntent(ACTION_OPEN_DOWNLOADS_FINISHED));
         }
 
         if (downloadDoneCount < 1) {
@@ -417,33 +432,38 @@ public class DownloadManagerService extends Service {
         downloadDoneCount++;
     }
 
-    public void notifyFailedDownload(String name) {
-        if (icDownloadDone == null) {
-            // TODO: use a proper icon for failed downloads
-            icDownloadDone = BitmapFactory.decodeResource(this.getResources(), android.R.drawable.stat_sys_download_done);
-        }
+    public void notifyFailedDownload(DownloadMission mission) {
+        if (!mDownloadNotificationEnable || mFailedDownloads.indexOfValue(mission) >= 0) return;
 
-        Builder notification = new Builder(this, getString(R.string.notification_channel_id))
-                .setAutoCancel(true)
-                .setLargeIcon(icDownloadDone)
-                .setSmallIcon(android.R.drawable.stat_sys_download_done)
-                .setContentIntent(PendingIntent.getService(this, (int) System.currentTimeMillis() + 1,
-                        new Intent(this, DownloadActivity.class)
-                                .setAction(Intent.ACTION_MAIN),
-                        PendingIntent.FLAG_UPDATE_CURRENT));
+        int id = downloadFailedNotificationID++;
+        mFailedDownloads.put(id, mission);
+
+        if (downloadFailedNotification == null) {
+            icDownloadFailed = BitmapFactory.decodeResource(this.getResources(), android.R.drawable.stat_sys_warning);
+            downloadFailedNotification = new Builder(this, getString(R.string.notification_channel_id))
+                    .setAutoCancel(true)
+                    .setLargeIcon(icDownloadFailed)
+                    .setSmallIcon(android.R.drawable.stat_sys_warning)
+                    .setContentIntent(mOpenDownloadList);
+        }
 
         if (android.os.Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
-            notification.setContentTitle(getString(R.string.app_name));
-            notification.setStyle(new NotificationCompat.BigTextStyle()
-                    .bigText(getString(R.string.download_failed).concat(": ").concat(name)));
+            downloadFailedNotification.setContentTitle(getString(R.string.app_name));
+            downloadFailedNotification.setStyle(new NotificationCompat.BigTextStyle()
+                    .bigText(getString(R.string.download_failed).concat(": ").concat(mission.name)));
         } else {
-            notification.setContentTitle(getString(R.string.download_failed));
-            notification.setContentText(name);
-            notification.setStyle(new NotificationCompat.BigTextStyle()
-                    .bigText(name));
+            downloadFailedNotification.setContentTitle(getString(R.string.download_failed));
+            downloadFailedNotification.setContentText(mission.name);
+            downloadFailedNotification.setStyle(new NotificationCompat.BigTextStyle()
+                    .bigText(mission.name));
         }
 
-        notificationManager.notify(downloadFailedNotificationID++, notification.build());
+        notificationManager.notify(id, downloadFailedNotification.build());
+    }
+
+    private PendingIntent makePendingIntent(String action) {
+        Intent intent = new Intent(this, DownloadManagerService.class).setAction(action);
+        return PendingIntent.getService(this, intent.hashCode(), intent, PendingIntent.FLAG_UPDATE_CURRENT);
     }
 
     private void manageObservers(Handler handler, boolean add) {
@@ -470,12 +490,26 @@ public class DownloadManagerService extends Service {
             manageObservers(handler, false);
         }
 
-        public void resetFinishedDownloadCount() {
-            if (notificationManager == null || downloadDoneNotification == null) return;
-            notificationManager.cancel(DOWNLOADS_NOTIFICATION_ID);
-            downloadDoneList.setLength(0);
-            downloadDoneCount = 0;
+        public void clearDownloadNotifications() {
+            if (notificationManager == null) return;
+            if (downloadDoneNotification != null) {
+                notificationManager.cancel(DOWNLOADS_NOTIFICATION_ID);
+                downloadDoneList.setLength(0);
+                downloadDoneCount = 0;
+            }
+            if (downloadFailedNotification != null) {
+                for (; downloadFailedNotificationID > DOWNLOADS_NOTIFICATION_ID; downloadFailedNotificationID--) {
+                    notificationManager.cancel(downloadFailedNotificationID);
+                }
+                mFailedDownloads.clear();
+                downloadFailedNotificationID++;
+            }
         }
+
+        public void enableNotifications(boolean enable) {
+            mDownloadNotificationEnable = enable;
+        }
+
     }
 
     public interface DMChecker {
diff --git a/app/src/main/java/us/shandian/giga/ui/adapter/MissionAdapter.java b/app/src/main/java/us/shandian/giga/ui/adapter/MissionAdapter.java
index 4dc40c420..8c332565b 100644
--- a/app/src/main/java/us/shandian/giga/ui/adapter/MissionAdapter.java
+++ b/app/src/main/java/us/shandian/giga/ui/adapter/MissionAdapter.java
@@ -20,6 +20,7 @@ import android.support.v7.app.AlertDialog;
 import android.support.v7.util.DiffUtil;
 import android.support.v7.widget.RecyclerView;
 import android.support.v7.widget.RecyclerView.ViewHolder;
+import android.support.v7.widget.RecyclerView.Adapter;
 import android.util.Log;
 import android.util.SparseArray;
 import android.view.LayoutInflater;
@@ -40,7 +41,6 @@ import org.schabi.newpipe.util.NavigationHelper;
 import java.io.File;
 import java.lang.ref.WeakReference;
 import java.util.ArrayList;
-import java.util.Locale;
 
 import us.shandian.giga.get.DownloadMission;
 import us.shandian.giga.get.FinishedMission;
@@ -53,9 +53,10 @@ import us.shandian.giga.util.Utility;
 import static android.content.Intent.FLAG_GRANT_PREFIX_URI_PERMISSION;
 import static android.content.Intent.FLAG_GRANT_READ_URI_PERMISSION;
 
-public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
+public class MissionAdapter extends Adapter<ViewHolder> {
     private static final SparseArray<String> ALGORITHMS = new SparseArray<>();
     private static final String TAG = "MissionAdapter";
+    private static final String UNDEFINED_SPEED = "--.-%";
 
     static {
         ALGORITHMS.put(R.id.md5, "MD5");
@@ -89,6 +90,7 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
                     case DownloadManagerService.MESSAGE_ERROR:
                     case DownloadManagerService.MESSAGE_FINISHED:
                         onServiceMessage(msg);
+                        break;
                 }
             }
         };
@@ -120,7 +122,10 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
         if (view instanceof ViewHolderHeader) return;
         ViewHolderItem h = (ViewHolderItem) view;
 
-        if (h.item.mission instanceof DownloadMission) mPendingDownloadsItems.remove(h);
+        if (h.item.mission instanceof DownloadMission) {
+            mPendingDownloadsItems.remove(h);
+            if (mPendingDownloadsItems.size() < 1) setAutoRefresh(false);
+        }
 
         h.popupMenu.dismiss();
         h.item = null;
@@ -153,10 +158,11 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
         h.item = item;
 
         Utility.FileType type = Utility.getFileType(item.mission.kind, item.mission.name);
+        long length = item.mission instanceof FinishedMission ? item.mission.length : ((DownloadMission) item.mission).getLength();
 
         h.icon.setImageResource(Utility.getIconForFileType(type));
         h.name.setText(item.mission.name);
-        h.size.setText(Utility.formatBytes(item.mission.length));
+        h.size.setText(Utility.formatBytes(length));
 
         h.progress.setColors(Utility.getBackgroundForFileType(mContext, type), Utility.getForegroundForFileType(mContext, type));
 
@@ -187,66 +193,60 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
     private void updateProgress(ViewHolderItem h) {
         if (h == null || h.item == null || h.item.mission instanceof FinishedMission) return;
 
+        long now = System.currentTimeMillis();
         DownloadMission mission = (DownloadMission) h.item.mission;
 
-        long now = System.currentTimeMillis();
-
-        if (h.lastTimeStamp == -1) {
-            h.lastTimeStamp = now;
-        }
-
-        if (h.lastDone == -1) {
-            h.lastDone = mission.done;
-        }
         if (h.lastCurrent != mission.current) {
             h.lastCurrent = mission.current;
-            h.lastDone = 0;
             h.lastTimeStamp = now;
+            h.lastDone = 0;
+        } else {
+            if (h.lastTimeStamp == -1) h.lastTimeStamp = now;
+            if (h.lastDone == -1) h.lastDone = mission.done;
         }
 
         long deltaTime = now - h.lastTimeStamp;
         long deltaDone = mission.done - h.lastDone;
         boolean hasError = mission.errCode != DownloadMission.ERROR_NOTHING;
 
-        if (hasError || deltaTime == 0 || deltaTime > 1000) {
-            // on error hide marquee or show if condition (mission.done < 1 || mission.unknownLength) is true
-            h.progress.setMarquee(!hasError && (mission.done < 1 || mission.unknownLength));
+        // on error hide marquee or show if condition (mission.done < 1 || mission.unknownLength) is true
+        h.progress.setMarquee(!hasError && (mission.done < 1 || mission.unknownLength));
 
-            float progress;
-            if (mission.unknownLength) {
-                progress = Float.NaN;
-                h.progress.setProgress(0f);
-            } else {
-                progress = (float) ((double) mission.done / mission.length);
-                if (mission.urls.length > 1 && mission.current < mission.urls.length) {
-                    progress = (progress / mission.urls.length) + ((float) mission.current / mission.urls.length);
-                }
+        float progress;
+        if (mission.unknownLength) {
+            progress = Float.NaN;
+            h.progress.setProgress(0f);
+        } else {
+            progress = (float) ((double) mission.done / mission.length);
+            if (mission.urls.length > 1 && mission.current < mission.urls.length) {
+                progress = (progress / mission.urls.length) + ((float) mission.current / mission.urls.length);
             }
+        }
 
-            if (hasError) {
-                if (Float.isNaN(progress) || Float.isInfinite(progress))
-                    h.progress.setProgress(1f);
-                h.status.setText(R.string.msg_error);
-            } else if (Float.isNaN(progress) || Float.isInfinite(progress)) {
-                h.status.setText("--.-%");
-            } else {
-                h.status.setText(String.format("%.2f%%", progress * 100));
-                h.progress.setProgress(progress);
-            }
+        if (hasError) {
+            if (Float.isNaN(progress) || Float.isInfinite(progress))
+                h.progress.setProgress(1f);
+            h.status.setText(R.string.msg_error);
+        } else if (Float.isNaN(progress) || Float.isInfinite(progress)) {
+            h.status.setText(UNDEFINED_SPEED);
+        } else {
+            h.status.setText(String.format("%.2f%%", progress * 100));
+            h.progress.setProgress(progress);
         }
 
         long length = mission.getLength();
 
-        int state = 0;
-        if (!mission.isFinished()) {
-            if (!mission.running) {
-                state = mission.enqueued ? 1 : 2;
-            } else if (mission.postprocessingRunning) {
-                state = 3;
-            }
+        int state;
+        if (!mission.running) {
+            state = mission.enqueued ? 1 : 2;
+        } else if (mission.postprocessingRunning) {
+            state = 3;
+        } else {
+            state = 0;
         }
 
         if (state != 0) {
+            // update state without download speed
             if (h.state != state) {
                 String statusStr;
                 h.state = state;
@@ -267,7 +267,7 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
                 }
 
                 h.size.setText(Utility.formatBytes(length).concat("  (").concat(statusStr).concat(")"));
-            } else if (deltaTime > 1000 && deltaDone > 0) {
+            } else if (deltaDone > 0) {
                 h.lastTimeStamp = now;
                 h.lastDone = mission.done;
             }
@@ -275,10 +275,10 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
             return;
         }
 
+        if (deltaDone > 0 && deltaTime > 0) {
+            float speed = (deltaDone * 1000f) / deltaTime;
 
-        if (deltaTime > 1000 && deltaDone > 0) {
-            float speed = (float) ((double) deltaDone / deltaTime);
-            String speedStr = Utility.formatSpeed(speed * 1000);
+            String speedStr = Utility.formatSpeed(speed);
             String sizeStr = Utility.formatBytes(length);
 
             h.size.setText(sizeStr.concat(" ").concat(speedStr));
@@ -325,6 +325,8 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
     private void onServiceMessage(@NonNull Message msg) {
         switch (msg.what) {
             case DownloadManagerService.MESSAGE_PROGRESS:
+                setAutoRefresh(true);
+                return;
             case DownloadManagerService.MESSAGE_ERROR:
             case DownloadManagerService.MESSAGE_FINISHED:
                 break;
@@ -339,8 +341,6 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
             if (msg.what == DownloadManagerService.MESSAGE_FINISHED) {
                 // DownloadManager should mark the download as finished
                 applyChanges();
-
-                mPendingDownloadsItems.remove(i);
                 return;
             }
 
@@ -396,7 +396,9 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
                 break;
             default:
                 if (mission.errCode >= 100 && mission.errCode < 600) {
-                    str.append("HTTP");
+                    str = new StringBuilder(8);
+                    str.append("HTTP ");
+                    str.append(mission.errCode);
                 } else if (mission.errObject == null) {
                     str.append("(not_decelerated_error_code)");
                 }
@@ -436,7 +438,7 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
                 case R.id.pause:
                     h.state = -1;
                     mDownloadManager.pauseMission(mission);
-                    notifyItemChanged(h.getAdapterPosition());
+                    updateProgress(h);
                     h.lastTimeStamp = -1;
                     h.lastDone = -1;
                     return true;
@@ -542,6 +544,43 @@ public class MissionAdapter extends RecyclerView.Adapter<ViewHolder> {
     }
 
 
+    private boolean mUpdaterRunning = false;
+    private final Runnable rUpdater = this::updater;
+
+    public void onPaused() {
+        setAutoRefresh(false);
+    }
+
+    private void setAutoRefresh(boolean enabled) {
+        if (enabled && !mUpdaterRunning) {
+            mUpdaterRunning = true;
+            updater();
+        } else if (!enabled && mUpdaterRunning) {
+            mUpdaterRunning = false;
+            mHandler.removeCallbacks(rUpdater);
+        }
+    }
+
+    private void updater() {
+        if (!mUpdaterRunning) return;
+
+        boolean running = false;
+        for (ViewHolderItem h : mPendingDownloadsItems) {
+            // check if the mission is running first
+            if (!((DownloadMission) h.item.mission).running) continue;
+
+            updateProgress(h);
+            running = true;
+        }
+
+        if (running) {
+            mHandler.postDelayed(rUpdater, 1000);
+        } else {
+            mUpdaterRunning = false;
+        }
+    }
+
+
     class ViewHolderItem extends RecyclerView.ViewHolder {
         DownloadManager.MissionItem item;
 
diff --git a/app/src/main/java/us/shandian/giga/ui/fragment/MissionsFragment.java b/app/src/main/java/us/shandian/giga/ui/fragment/MissionsFragment.java
index f04361f19..aa9c497f1 100644
--- a/app/src/main/java/us/shandian/giga/ui/fragment/MissionsFragment.java
+++ b/app/src/main/java/us/shandian/giga/ui/fragment/MissionsFragment.java
@@ -51,7 +51,7 @@ public class MissionsFragment extends Fragment {
         @Override
         public void onServiceConnected(ComponentName name, IBinder binder) {
             mBinder = (DownloadManagerService.DMBinder) binder;
-            mBinder.resetFinishedDownloadCount();
+            mBinder.clearDownloadNotifications();
 
             mAdapter = new MissionAdapter(mActivity, mBinder.getDownloadManager(), mClear, mEmpty);
             mAdapter.deleterLoad(mBundle, getView());
@@ -59,6 +59,7 @@ public class MissionsFragment extends Fragment {
             mBundle = null;
 
             mBinder.addMissionEventListener(mAdapter.getMessenger());
+            mBinder.enableNotifications(false);
 
             updateList();
         }
@@ -130,7 +131,7 @@ public class MissionsFragment extends Fragment {
     @Override
     public void onAttach(Activity activity) {
         super.onAttach(activity);
-        
+
         mActivity = activity;
     }
 
@@ -141,6 +142,7 @@ public class MissionsFragment extends Fragment {
         if (mBinder == null || mAdapter == null) return;
 
         mBinder.removeMissionEventListener(mAdapter.getMessenger());
+        mBinder.enableNotifications(true);
         mActivity.unbindService(mConnection);
         mAdapter.deleterDispose(null);
 
@@ -181,7 +183,7 @@ public class MissionsFragment extends Fragment {
         // destroy all created views in the recycler
         mList.setAdapter(null);
         mAdapter.notifyDataSetChanged();
-        
+
         // re-attach the adapter in grid/lineal mode
         mAdapter.setLinear(mLinear);
         mList.setAdapter(mAdapter);
@@ -201,14 +203,13 @@ public class MissionsFragment extends Fragment {
             mAdapter.deleterDispose(outState);
             mForceUpdate = true;
             mBinder.removeMissionEventListener(mAdapter.getMessenger());
-               
         }
     }
 
     @Override
     public void onResume() {
         super.onResume();
-                                                 
+
         if (mAdapter != null) {
             mAdapter.deleterResume();
 
@@ -219,5 +220,13 @@ public class MissionsFragment extends Fragment {
 
             mBinder.addMissionEventListener(mAdapter.getMessenger());
         }
+        if (mBinder != null) mBinder.enableNotifications(false);
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+        if (mAdapter != null) mAdapter.onPaused();
+        if (mBinder != null) mBinder.enableNotifications(true);
     }
 }
diff --git a/app/src/main/res/values/settings_keys.xml b/app/src/main/res/values/settings_keys.xml
index 2973b69ef..5125752b4 100644
--- a/app/src/main/res/values/settings_keys.xml
+++ b/app/src/main/res/values/settings_keys.xml
@@ -176,7 +176,9 @@
     <string name="default_file_charset_value" translatable="false">@string/charset_most_special_characters_value</string>
     
     <string name="downloads_max_retry" translatable="false">downloads_max_retry</string>
+    <string name="downloads_max_retry_default" translatable="false">3</string>
     <string-array name="downloads_max_retry_list" translatable="false">
+        <item translatable="true">@string/minimize_on_exit_none_description</item>
         <item>1</item>
         <item>2</item>
         <item>3</item>
@@ -186,9 +188,8 @@
         <item>10</item>
         <item>15</item>
     </string-array>
-    
-    <string name="default_max_retry" translatable="false">3</string>
-    <string name="cross_network_downloads" translatable="false">cross_network_downloads</string>
+
+    <string name="downloads_cross_network" translatable="false">cross_network_downloads</string>
 
     <string name="default_download_threads" translatable="false">default_download_threads</string>
 
diff --git a/app/src/main/res/xml/download_settings.xml b/app/src/main/res/xml/download_settings.xml
index 7175ae711..e7faf40dd 100644
--- a/app/src/main/res/xml/download_settings.xml
+++ b/app/src/main/res/xml/download_settings.xml
@@ -30,7 +30,7 @@
         android:title="@string/settings_file_replacement_character_title"/>
 
     <ListPreference
-        android:defaultValue="@string/default_max_retry"
+        android:defaultValue="@string/downloads_max_retry_default"
         android:entries="@array/downloads_max_retry_list"
         android:entryValues="@array/downloads_max_retry_list"
         android:key="@string/downloads_max_retry"
@@ -39,7 +39,7 @@
 
     <SwitchPreference
         android:defaultValue="false"
-        android:key="@string/cross_network_downloads"
+        android:key="@string/downloads_cross_network"
         android:summary="@string/pause_downloads_on_mobile_desc"
         android:title="@string/pause_downloads_on_mobile" />