Mobile app that changes Bluetooth Device Audio Codec to SBC. Created with a little bit of Reverse Engineering.
This app uses hidden Android APIs like android.bluetooth.BluetoothA2dp. App can be compiled when these APIs are exposed. You can replace android.jar file in SDK directory in order to use "unlocked" Android SDK: https://github.com/anggrayudi/android-hidden-api
Following code changes Bluetooth Audio Codec to SBC. Method names was extracted by doing some RE on official Settings app: https://github.com/aosp-mirror/platform_packages_apps_settings/tree/master/src/com/android/settings
private BluetoothProfile.ServiceListener mProfileListener = new BluetoothProfile.ServiceListener() {
public void onServiceConnected(int profile, BluetoothProfile proxy) {
if (profile == BluetoothProfile.A2DP) {
a2dp = (BluetoothA2dp) proxy;
BluetoothDevice device = a2dp.getActiveDevice();
BluetoothCodecStatus status = a2dp.getCodecStatus(device);
BluetoothCodecConfig config = status.getCodecConfig();
int codec = config.getCodecType();
BluetoothCodecConfig newConfig = new BluetoothCodecConfig(0,
1000 * 1000,
SAMPLE_RATE_44100,
BITS_PER_SAMPLE_16,
CHANNEL_MODE_STEREO,
32771,
49152,
0,
0);
a2dp.setCodecConfigPreference(device, newConfig);
BluetoothCodecStatus updatedStatus = a2dp.getCodecStatus(device);
BluetoothCodecConfig updatedConfig = updatedStatus.getCodecConfig();
runOnUiThread(() -> codecNameTextView.setText("Codec2:" + updatedConfig.toString()));
MainActivity.this.finish();
System.exit(0);
}
}