diff --git a/app/src/main/java/net/yrom/screenrecorder/MainActivity.java b/app/src/main/java/net/yrom/screenrecorder/MainActivity.java
index caaaf4c..3b24e82 100644
--- a/app/src/main/java/net/yrom/screenrecorder/MainActivity.java
+++ b/app/src/main/java/net/yrom/screenrecorder/MainActivity.java
@@ -44,6 +44,7 @@
 import android.widget.Button;
 import android.widget.SpinnerAdapter;
 import android.widget.Toast;
+import android.widget.ToggleButton;
 
 import net.yrom.screenrecorder.view.NamedSpinner;
 
@@ -67,6 +68,7 @@ public class MainActivity extends Activity {
     // members below will be initialized in onCreate()
     private MediaProjectionManager mMediaProjectionManager;
     private Button mButton;
+    private ToggleButton mAudioToggle;
     private NamedSpinner mVieoResolution;
     private NamedSpinner mVideoFramerate;
     private NamedSpinner mIFrameInterval;
@@ -113,6 +115,9 @@ protected void onCreate(Bundle savedInstanceState) {
             mAudioCodec.setAdapter(codecsAdapter);
             restoreSelections(mAudioCodec, mAudioChannelCount);
         });
+        mAudioToggle.setChecked(
+                PreferenceManager.getDefaultSharedPreferences(getApplicationContext())
+                        .getBoolean(getResources().getResourceEntryName(mAudioToggle.getId()), true));
     }
 
     @Override
@@ -142,8 +147,8 @@ protected void onActivityResult(int requestCode, int resultCode, Intent data) {
             }
 
             VideoEncodeConfig video = createVideoConfig();
-            AudioEncodeConfig audio = createAudioConfig();
-            if (video == null || audio == null) {
+            AudioEncodeConfig audio = createAudioConfig(); // audio can be null
+            if (video == null) {
                 toast("Create ScreenRecorder failure");
                 mediaProjection.stop();
                 return;
@@ -207,6 +212,7 @@ public void onRecording(long presentationTimeUs) {
     }
 
     private AudioEncodeConfig createAudioConfig() {
+        if (!mAudioToggle.isChecked()) return null;
         String codec = getSelectedAudioCodec();
         if (codec == null) {
             return null;
@@ -246,11 +252,14 @@ private static File getSavingDir() {
     @Override
     public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
         if (requestCode == REQUEST_PERMISSIONS) {
-            // we request 2 permissions
-            if (grantResults.length == 2
-                    && grantResults[0] == PackageManager.PERMISSION_GRANTED
-                    && grantResults[1] == PackageManager.PERMISSION_GRANTED) {
+            int granted = PackageManager.PERMISSION_GRANTED;
+            for (int r : grantResults) {
+                granted |= r;
+            }
+            if (granted == PackageManager.PERMISSION_GRANTED) {
                 startCaptureIntent();
+            } else {
+                toast("No Permission!");
             }
         }
     }
@@ -285,6 +294,12 @@ private void bindViews() {
         mAudioProfile = findViewById(R.id.aac_profile);
         mAudioChannelCount = findViewById(R.id.audio_channel_count);
 
+        mAudioToggle = findViewById(R.id.with_audio);
+        mAudioToggle.setOnCheckedChangeListener((buttonView, isChecked) ->
+                findViewById(R.id.audio_format_chooser)
+                        .setVisibility(isChecked ? View.VISIBLE : View.GONE)
+        );
+
         if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {
             mOrientation.setSelectedPosition(1);
         }
@@ -351,16 +366,22 @@ private void cancelRecorder() {
 
     @TargetApi(M)
     private void requestPermissions() {
-        if (!shouldShowRequestPermissionRationale(WRITE_EXTERNAL_STORAGE)
-                && !shouldShowRequestPermissionRationale(RECORD_AUDIO)) {
-            requestPermissions(new String[]{WRITE_EXTERNAL_STORAGE, RECORD_AUDIO}, REQUEST_PERMISSIONS);
+        String[] permissions = mAudioToggle.isChecked()
+                ? new String[]{WRITE_EXTERNAL_STORAGE, RECORD_AUDIO}
+                : new String[]{WRITE_EXTERNAL_STORAGE};
+        boolean showRationale = false;
+        for (String perm : permissions) {
+            showRationale |= shouldShowRequestPermissionRationale(perm);
+        }
+        if (!showRationale) {
+            requestPermissions(permissions, REQUEST_PERMISSIONS);
             return;
         }
         new AlertDialog.Builder(this)
                 .setMessage("Using your mic to record audio and your sd card to save video file")
                 .setCancelable(false)
                 .setPositiveButton(android.R.string.ok, (dialog, which) ->
-                        requestPermissions(new String[]{WRITE_EXTERNAL_STORAGE, RECORD_AUDIO}, REQUEST_PERMISSIONS))
+                        requestPermissions(permissions, REQUEST_PERMISSIONS))
                 .setNegativeButton(android.R.string.cancel, null)
                 .create()
                 .show();
@@ -369,7 +390,7 @@ private void requestPermissions() {
     private boolean hasPermissions() {
         PackageManager pm = getPackageManager();
         String packageName = getPackageName();
-        int granted = pm.checkPermission(RECORD_AUDIO, packageName)
+        int granted = (mAudioToggle.isChecked() ? pm.checkPermission(RECORD_AUDIO, packageName) : PackageManager.PERMISSION_GRANTED)
                 | pm.checkPermission(WRITE_EXTERNAL_STORAGE, packageName);
         return granted == PackageManager.PERMISSION_GRANTED;
     }
@@ -787,6 +808,7 @@ private void saveSelections() {
         }) {
             saveSelectionToPreferences(edit, spinner);
         }
+        edit.putBoolean(getResources().getResourceEntryName(mAudioToggle.getId()), mAudioToggle.isChecked());
         edit.apply();
     }
 
@@ -817,7 +839,7 @@ public void onReceive(Context context, Intent intent) {
             if (ACTION_STOP.equals(intent.getAction())) {
                 stopRecorder();
             }
-            Toast.makeText(context, "Recorder stopped!", Toast.LENGTH_SHORT).show();
+            Toast.makeText(context, "Recorder stopped!\n Saved file " + file, Toast.LENGTH_LONG).show();
             StrictMode.VmPolicy vmPolicy = StrictMode.getVmPolicy();
             try {
                 // disable detecting FileUriExposure on public file
diff --git a/app/src/main/java/net/yrom/screenrecorder/Notifications.java b/app/src/main/java/net/yrom/screenrecorder/Notifications.java
index f1ffd73..e5fa1d2 100644
--- a/app/src/main/java/net/yrom/screenrecorder/Notifications.java
+++ b/app/src/main/java/net/yrom/screenrecorder/Notifications.java
@@ -85,7 +85,7 @@ private Notification.Builder getBuilder() {
     @TargetApi(O)
     private void createNotificationChannel() {
         NotificationChannel channel =
-                new NotificationChannel(CHANNEL_ID, CHANNEL_NAME, NotificationManager.IMPORTANCE_DEFAULT);
+                new NotificationChannel(CHANNEL_ID, CHANNEL_NAME, NotificationManager.IMPORTANCE_LOW);
         channel.setShowBadge(false);
         getNotificationManager().createNotificationChannel(channel);
     }
diff --git a/app/src/main/java/net/yrom/screenrecorder/ScreenRecorder.java b/app/src/main/java/net/yrom/screenrecorder/ScreenRecorder.java
index 9139c82..88d68e7 100644
--- a/app/src/main/java/net/yrom/screenrecorder/ScreenRecorder.java
+++ b/app/src/main/java/net/yrom/screenrecorder/ScreenRecorder.java
@@ -90,7 +90,7 @@ public ScreenRecorder(VideoEncodeConfig video,
         mMediaProjection = mp;
         mDstPath = dstPath;
         mVideoEncoder = new VideoEncoder(video);
-        mAudioEncoder = new MicRecorder(audio);
+        mAudioEncoder = audio == null ? null : new MicRecorder(audio);
 
     }
 
@@ -331,12 +331,13 @@ private void resetAudioOutputFormat(MediaFormat newFormat) {
     }
 
     private void startMuxerIfReady() {
-        if (mMuxerStarted || mVideoOutputFormat == null || mAudioOutputFormat == null) {
+        if (mMuxerStarted || mVideoOutputFormat == null
+                || (mAudioEncoder != null && mAudioOutputFormat == null)) {
             return;
         }
 
         mVideoTrackIndex = mMuxer.addTrack(mVideoOutputFormat);
-        mAudioTrackIndex = mMuxer.addTrack(mAudioOutputFormat);
+        mAudioTrackIndex = mAudioEncoder == null ? INVALID_INDEX : mMuxer.addTrack(mAudioOutputFormat);
         mMuxer.start();
         mMuxerStarted = true;
         if (VERBOSE) Log.i(TAG, "Started media muxer, videoIndex=" + mVideoTrackIndex);
@@ -349,9 +350,11 @@ private void startMuxerIfReady() {
             int index = mPendingVideoEncoderBufferIndices.poll();
             muxVideo(index, info);
         }
-        while ((info = mPendingAudioEncoderBufferInfos.poll()) != null) {
-            int index = mPendingAudioEncoderBufferIndices.poll();
-            muxAudio(index, info);
+        if (mAudioEncoder != null) {
+            while ((info = mPendingAudioEncoderBufferInfos.poll()) != null) {
+                int index = mPendingAudioEncoderBufferIndices.poll();
+                muxAudio(index, info);
+            }
         }
         if (VERBOSE) Log.i(TAG, "Mux pending video output buffers done.");
     }
@@ -390,6 +393,8 @@ public void onOutputFormatChanged(BaseEncoder codec, MediaFormat format) {
     }
 
     private void prepareAudioEncoder() throws IOException {
+        final MicRecorder micRecorder = mAudioEncoder;
+        if (micRecorder == null) return;
         AudioEncoder.Callback callback = new AudioEncoder.Callback() {
             boolean ranIntoError = false;
 
@@ -422,8 +427,8 @@ public void onError(Encoder codec, Exception e) {
 
 
         };
-        mAudioEncoder.setCallback(callback);
-        mAudioEncoder.prepare();
+        micRecorder.setCallback(callback);
+        micRecorder.prepare();
     }
 
     private void signalStop(boolean stopWithEOS) {
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index 4c317c6..bb9e3a0 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -1,4 +1,4 @@
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:id="@+id/container"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
@@ -79,57 +79,73 @@
                 android:layout_marginTop="8dp"
                 android:entries="@array/orientations" />
 
-            <TextView
-                style="?android:attr/titleTextStyle"
+            <LinearLayout
+                android:id="@+id/audio_format_chooser"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_marginTop="16dp"
-                android:text="Audio Encode Config (H.264 AAC)" />
-
-            <net.yrom.screenrecorder.view.NamedSpinner
-                android:id="@+id/audio_codec"
-                android:name="Audio Encoder"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_marginTop="8dp" />
-
-            <net.yrom.screenrecorder.view.NamedSpinner
-                android:id="@+id/audio_channel_count"
-                android:name="Channels"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_marginTop="8dp"
-                android:entries="@array/audio_channels" />
-
-            <net.yrom.screenrecorder.view.NamedSpinner
-                android:id="@+id/sample_rate"
-                android:name="Sample Rate (HZ)"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_marginTop="8dp" />
-
-            <net.yrom.screenrecorder.view.NamedSpinner
-                android:id="@+id/audio_bitrate"
-                android:name="Bitrate (kbps)"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_marginTop="8dp" />
-
-            <net.yrom.screenrecorder.view.NamedSpinner
-                android:id="@+id/aac_profile"
-                android:name="AAC Profile"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_marginTop="8dp" />
-
+                android:orientation="vertical">
+
+                <TextView
+                    style="?android:attr/titleTextStyle"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="Audio Encode Config (H.264 AAC)" />
+
+                <net.yrom.screenrecorder.view.NamedSpinner
+                    android:id="@+id/audio_codec"
+                    android:name="Audio Encoder"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:layout_marginTop="8dp" />
+
+                <net.yrom.screenrecorder.view.NamedSpinner
+                    android:id="@+id/audio_channel_count"
+                    android:name="Channels"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:layout_marginTop="8dp"
+                    android:entries="@array/audio_channels" />
+
+                <net.yrom.screenrecorder.view.NamedSpinner
+                    android:id="@+id/sample_rate"
+                    android:name="Sample Rate (HZ)"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:layout_marginTop="8dp" />
+
+                <net.yrom.screenrecorder.view.NamedSpinner
+                    android:id="@+id/audio_bitrate"
+                    android:name="Bitrate (kbps)"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:layout_marginTop="8dp" />
+
+                <net.yrom.screenrecorder.view.NamedSpinner
+                    android:id="@+id/aac_profile"
+                    android:name="AAC Profile"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:layout_marginTop="8dp" />
+            </LinearLayout>
         </LinearLayout>
     </ScrollView>
 
+    <ToggleButton
+        android:id="@+id/with_audio"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_above="@+id/record_button"
+        android:layout_alignParentEnd="true"
+        android:checked="true"
+        android:textOff="Without Audio"
+        android:textOn="With Audio" />
+
     <Button
         android:id="@+id/record_button"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_gravity="right|bottom"
+        android:layout_alignParentBottom="true"
+        android:layout_alignParentEnd="true"
         android:text="Start Recorder" />
-
-</FrameLayout>
+</RelativeLayout>