Combine parts of SCO with parts of A2DP

Question

I'm looking to pair A2DP stereo sound with the interrupt functionality of AudioManager's MODE_IN_COMMUNICATION. The purpose of this pairing is to insert snippets of custom music into AM/FM broadcasts by using the music as something that "dials" the Android device and stops the AM/FM broadcast.

I have this working decently with SCO using the following code to start the "phone call".

Here is the AudioManager code:

AudioManager localAudioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
localAudioManager.setMode(0);
localAudioManager.setBluetoothScoOn(true);
localAudioManager.startBluetoothSco();
localAudioManager.setMode(AudioManager.MODE_IN_COMMUNICATION);

Here is the MediaPlayer I'm trying to play:

MediaPlayer mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioAttributes(new AudioAttributes.Builder()
    .setUsage(AudioAttributes.USAGE_MEDIA)
    .setContentType(AudioAttributes.CONTENT_TYPE_SPEECH)
    .build());

mediaPlayer.setDataSource("https://wmbr.org/WMBR_Archive_128.m3u");
mediaPlayer.prepare();
mediaPlayer.start();

The audio produced by this code is low-quality and mono as opposed to stereo. I would like to change that.

The issue is that the Android Dev site for startBluetoothSco says:

Even if a SCO connection is established, the following restrictions apply on audio output streams so that they can be routed to SCO headset: - the stream type must be STREAM_VOICE_CALL - the format must be mono - the sampling must be 16kHz or 8kHz

Is there any existing way to combine stereo sound and the interrupt functionality?

Additional context: in this answer it seems that MODE_IN_COMMUNICATION and MODE_IN_CALL use the PHONE routing strategy. He also says

If your BT accessory supports the Hands-free profile it will use a SCO link for the voice audio, and the ACL channel used for A2DP should be closed to avoid interference between the two.

I'm assuming this means my only option is a custom routing strategy, and I'm not sure what that entails.

Combine parts of SCO with parts of A2DP

0 Answers0