@Override
 protected void onPause() {
   if (mAudioUtils != null) {
     mAudioUtils.pauseAudio();
   }
   super.onPause();
 }
 @Override
 protected void onDestroy() {
   if (mAudioUtils != null) {
     mAudioUtils.clearResources();
   }
   super.onDestroy();
 }
 @SuppressWarnings("unused")
 @OnClick(R.id.display_audio_play_pause_button)
 public void playPauseAudio() {
   mAudioUtils.toggle();
 }