Built-in AEC cancels human voice — how to configure correctly?

Samsung Developer Program
1

We are testing built-in AEC (Acoustic Echo Canceler) on Samsung Tab A9+ (Model: SM-X210, Android 10).

When AEC is enabled, the human voice is significantly suppressed during music playback from a separate app (B.apk).

Our goal is to enable AEC while preserving the human voice clearly, even when music is playing.

Setup

  • apk – Recorder with AEC and NS enabled

if (android_recorder == null) {

AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);

audioManager.setMode(AudioManager.MODE_IN_COMMUNICATION); // Required for AEC?

android_recorder = new AudioRecord(

      MediaRecorder.AudioSource.VOICE_COMMUNICATION, // AEC-supported source

      16000,

      AudioFormat.CHANNEL_IN_MONO,

      AudioFormat.ENCODING_PCM_16BIT,

      bufferSize * 2

);

}

​

// Enable built-in AEC

if (AcousticEchoCanceler.isAvailable()) {

AcousticEchoCanceler aec = AcousticEchoCanceler.create(android_recorder.getAudioSessionId());

if (aec != null) {

  aec.setEnabled(true);

  Log.d(TAG, "AEC enabled: " + aec.getEnabled());

}

}

​

// Enable Noise Suppressor

if (NoiseSuppressor.isAvailable()) {

NoiseSuppressor ns = NoiseSuppressor.create(android_recorder.getAudioSessionId());

if (ns != null) {

  ns.setEnabled(true);

  Log.d(TAG, "NS enabled: " + ns.getEnabled());

}

}

​

android_recorder.startRecording();

android_recorder.read(buffer, 0, bufferSize, AudioRecord.READ_BLOCKING);

  • apk – Playback using ExoPlayer

AudioAttributes audioAttributes = new AudioAttributes.Builder()

  .setUsage(C.USAGE_MEDIA) // Also tried C.USAGE_VOICE_COMMUNICATION

  .setContentType(C.CONTENT_TYPE_MUSIC)

  .build();

​

player = new SimpleExoPlayer.Builder(context)

  .setAudioAttributes(audioAttributes, /* handleAudioFocus= */ false)

  .build();

​

player.setPlayWhenReady(false);

Questions:

  • Is there any configuration we are missing to allow AEC to work correctly, while keeping the human voice intact?
  • Do we need any specific KNOX permissions?
  • How to capture audio playback for AEC to function correctly?
  • Can you provide us with sample code?