I am building an android app, having feature of capturing sound through microphone and playing it through headphone. For this, I have used \"AudioRecord\" and \"AudioTrack\"
This worked for me
mediaRecorder = new MediaRecorder();
mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.DEFAULT);
mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);
mediaRecorder.setOutputFile(Environment.getExternalStorageDirectory()
.getAbsolutePath() + "/record.mp3");
mediaRecorder.prepare();
mediaRecorder.start();