Encode Audio Byte[] Array to Mp3 in Android Studio

Question

i hava a byte array which i am able to play successfully with AudioTrack. I am trying to encode or convert the byte array to an mp3 file. Since Android sdk doesnt support mp3 encoding, i am using Lame via this library (https://github.com/nwaldispuehl/java-lame). The Output mp3 plays noise only.

public void encodePcmToMp3(byte[] pcm) {
    LameEncoder encoder = new LameEncoder(new javax.sound.sampled.AudioFormat(44100.0f, 16, 1, true, true), 256, MPEGMode.MONO, Lame.QUALITY_HIGHEST, false);

    ByteArrayOutputStream mp3 = new ByteArrayOutputStream();
    byte[] buffer = new byte[encoder.getPCMBufferSize()];

    int bytesToTransfer = Math.min(buffer.length, pcm.length);
    int bytesWritten;
    int currentPcmPosition = 0;

     while (0 < (bytesWritten = encoder.encodeBuffer(pcm, currentPcmPosition, bytesToTransfer, buffer))) {
        currentPcmPosition += bytesToTransfer;
        bytesToTransfer = Math.min(buffer.length, pcm.length - currentPcmPosition);
        Log.e("logmessage", "current position: " + currentPcmPosition);
        mp3.write(buffer, 0, bytesWritten);
    }

    encoder.close();

    File file = new File("/storage/emulated/0/bajj/gtm.mp3");
    if (!file.exists()) {
        try {
            file.createNewFile();
        } catch (IOException e) {
            e.printStackTrace();
            Log.e("logmessage", "cannot create file");
        }

        FileOutputStream stream = null;
        try {
            stream = new FileOutputStream("/storage/emulated/0/bajj/gtm.mp3");
            stream.write(mp3.toByteArray());
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
 //   return mp3.toByteArray();
}

The Output mp3 plays noise only.