mRecorder = new MediaRecorder();
mRecorder.setAudioSource(MediaRecorder.AudioSource.OUTPUT); //Doesn't work
mRecorder.setAudioChannels(2);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mRecorder.setOutputFile(mFileName);
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);

try
{
    mRecorder.prepare();
}
catch (IOException e)
{
    Log.e(LOG_TAG, "prepare() failed");
}

mRecorder.start();

try
{
    File tempMp3 = File.createTempFile(filename, "mp3", Environment.getExternalStorageDirectory());
    this.fos = new FileOutputStream(tempMp3);
    this.visualizer.setCaptureSize(Visualizer.getCaptureSizeRange()[1]);
    this.visualizer.setDataCaptureListener(new Visualizer.OnDataCaptureListener() {
        @Override
        public void onWaveFormDataCapture(Visualizer visualizer, byte[] waveform, int samplingRate) {
            try
            {
                System.out.println("WAVEFORM " + waveform);
                fos.write(waveform); //When i close the file it is correct but have no sense for audio players
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
        }

        @Override
        public void onFftDataCapture(Visualizer visualizer, byte[] fft, int samplingRate) {}
    }, Visualizer.getMaxCaptureRate() / 2, true, false);
    this.visualizer.setEnabled(true);
}
catch (Exception e)
{
    System.out.println(e.getMessage());
}