When I run my Xamarin Forms application with the MediaPlayer API of the error and the program stops running from these lines below;

player.SetOnBufferingUpdateListener(this);
player.SetOnCompletionListener(this);
player.SetOnErrorListener(this);
player.SetOnPreparedListener(this);
player.SetOnSeekCompleteListener(this);

Note if I comment the lines above my application works, but with the lines commented above I will not have the function to go through all the songs.

using Android.App;
using Android.Media;
using Android.OS;
using Android.Runtime;
using Android.Util;
using Android.Views;
using Android.Widget;
using Java.Lang;
using System.IO;
using static Android.Media.MediaPlayer;

namespace AppExemploMediaPlayer
{
[Activity(Label = "AppExemploMediaPlayer", MainLauncher = true)]
public class MainActivity : Activity, IOnPreparedListener, IOnCompletionListener, IOnSeekCompleteListener, IOnBufferingUpdateListener, IOnErrorListener
{
private MediaPlayer player;
private MediaPlayer nextPlayer;
private TextView tvTime;
private long currentTime;
private long duration;
private bool isPlaying;

Button playButton;
Button pauseButton;

protected override void OnCreate(Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);

    // Set our view from the "main" layout resource
    SetContentView(Resource.Layout.Main);

    tvTime = (TextView)FindViewById(Resource.Id.tvTime);

    if(savedInstanceState != null)
    {
        duration = savedInstanceState.GetLong("duration");
        currentTime = savedInstanceState.GetLong("currentTime");
        isPlaying = savedInstanceState.GetBoolean("isPlaying");

        if (isPlaying)
        {
            //playButton.Click();
        }
    }

    playButton = FindViewById<Button>(Resource.Id.btnPlay);

    pauseButton = FindViewById<Button>(Resource.Id.btnPause);
    Button stopButton = FindViewById<Button>(Resource.Id.btnStop);

    playButton.Click += delegate {

        if (player == null)
        {
            try
            {                        
                var asset = Assets.OpenFd("tubarao.mp3");
                player = new MediaPlayer();
                player.SetDataSource(asset.FileDescriptor, asset.StartOffset, asset.Length);
                player.PrepareAsync();

                nextPlayer = new MediaPlayer();
                nextPlayer.SetAudioStreamType(Android.Media.Stream.Music);
                nextPlayer.SetDataSource("http://www.nossaquelegal.com.br/musica/starwars.mp3");
                nextPlayer.PrepareAsync();

                // ERRO AO EXECUTAR ESTAS INSTRUÇÕES
                player.SetOnBufferingUpdateListener(this);
                player.SetOnCompletionListener(this);
                player.SetOnErrorListener(this);
                player.SetOnPreparedListener(this);
                player.SetOnSeekCompleteListener(this);

            }
            catch (IllegalArgumentException e) { e.PrintStackTrace(); }
            catch (SecurityException e) { e.PrintStackTrace(); }
            catch (IllegalStateException e) { e.PrintStackTrace(); }
            catch (IOException e) { e.Message.ToString(); }
        }
        else
        {
            player.Start();
        }
    };
}

protected override void OnSaveInstanceState(Bundle outState)
{
    base.OnSaveInstanceState(outState);

    outState.PutLong("duration", duration);
    outState.PutLong("currentTime", currentTime);
    outState.PutBoolean("isPlaying", isPlaying);
}

protected override void OnPause()
{
    base.OnPause();

    if(player != null)
    {
        duration = player.Duration;
        currentTime = player.CurrentPosition;
    }
}

protected override void OnDestroy()
{
    base.OnDestroy();

    if(player != null)
    {
        player.Stop();
        player.Release();
        player = null;
    }
}

public void pauseMusic(View v)
{
    isPlaying = false;

    if (player != null)
    {
        player.Pause();
    }
}

public void stopMusic(View v)
{
    isPlaying = false;

    if (player != null)
    {
        player.Stop();
        player.Release();
        player = null;
        currentTime = 0;
    }
}

/* LISTENERS */
public virtual void OnPrepared(MediaPlayer mp)
{
    Log.Info("Script", "OnPrepared");

    isPlaying = true;

    mp.Start();
    mp.SetNextMediaPlayer(nextPlayer);
    mp.SetVolume(1, 1);
    mp.SeekTo((int)currentTime);
}

public virtual void OnCompletion(MediaPlayer mp)
{
    Log.Info("Script", "OnCompletion");

    mp.Start();
    mp.SetNextMediaPlayer(nextPlayer);

}

public virtual void OnSeekComplete(MediaPlayer mp)
{
    Log.Info("Script", "OnSeekComplete");
}

public virtual void OnBufferingUpdate(MediaPlayer mp, int percent)
{
    Log.Info("Script", "OnBufferingUpdate");
}

public virtual bool OnError(MediaPlayer mp, [GeneratedEnum] MediaError what, int extra)
{
    Log.Info("Script", "OnError");
    return false;
}

}

}