Видео не отображается с 2 экземплярами медиаплеера

Я пытаюсь использовать два экземпляра медиаплеера. Когда воспроизводится первый экземпляр, второй экземпляр подготавливается в другом потоке. И когда первый экземпляр завершает файл, запускается второй экземпляр.

Проблема: второй экземпляр воспроизводит только аудио, видео не видно.

Наблюдение: Если я подготовлю второй экземпляр с тем же держателем поверхности, что и первый, и начну после завершения первого экземпляра, все будет работать нормально. Вот код

package com.THER;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import com.THER.MessengerServiceActivities.IncomingHandler;
import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.media.MediaPlayer.OnPreparedListener;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.os.Messenger;
import android.os.RemoteException;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;
import android.view.View;
import android.widget.VideoView;
import android.widget.ViewSwitcher;

public class MediaPlayerActivity extends Activity implements OnCompletionListener, Callback, OnPreparedListener {

private MediaPlayer mMediaPlayer1 = null;
    private SurfaceView mPreview1;
    private SurfaceHolder holder1;
    private ViewSwitcher switcher;

    Integer counter = 0;
    Integer played_files = 1;
    private MediaPlayer mMediaPlayer2 = null;
    private SurfaceView mPreview2;
    private SurfaceHolder holder2;
    boolean mIsBound;
    boolean finish_flag = false;
    /** Messenger for communicating with service. */
    Messenger mService = null;


    @Override
    protected void onCreate(Bundle savedInstanceState) {

        Intent intent; 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.videoview);
        doBindService();
        intent = getIntent();
        counter=intent.getIntExtra("counter",counter);


        mPreview1 =(SurfaceView)findViewById(R.id.surfaceView1);
        holder1 = mPreview1.getHolder();
        holder1.addCallback(this);  
        holder1.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

        mPreview2 =(SurfaceView)findViewById(R.id.surfaceView2);
        holder2 = mPreview2.getHolder();
        holder2.addCallback(this);  
        holder2.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

        mMediaPlayer1 = new MediaPlayer();
        mMediaPlayer1.setScreenOnWhilePlaying(true);
        mMediaPlayer2 = new MediaPlayer();
        mMediaPlayer2.setScreenOnWhilePlaying(true);
        try {

                mMediaPlayer1.setDataSource("/sdcard/1.mp4");
                mMediaPlayer1.setDisplay(holder1);

            } catch (IllegalArgumentException e) {
                    // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IllegalStateException e) {
                    // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                    // TODO Auto-generated catch block
                e.printStackTrace();
            }



        mMediaPlayer1.setOnCompletionListener(this);
        mMediaPlayer1.setOnPreparedListener(this);
        //mMediaPlayer2.setOnPreparedListener(this);
        mMediaPlayer2.setOnCompletionListener(this);




        }
    private class MediaPlayerTask extends AsyncTask<MediaPlayer, Void, String> implements OnCompletionListener {

            String file;
            private SurfaceHolder holder;
        @Override
            protected String doInBackground(MediaPlayer... mp1) {
                // TODO Auto-generated method stub
             //mp1[0].reset();
             if(counter%2 == 0)
             {
                file = "/sdcard/2.mp4";
                holder = holder2;
             }
             else
             {
                file = "/sdcard/1.mp4";
                holder = holder1;
             }

            try {

                    mp1[0].reset();
                    mp1[0].setDataSource(file);
                    mp1[0].setDisplay(holder);
                    mp1[0].prepare();
                    mp1[0].setOnCompletionListener(this);
                    //mp1[0].start();

            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            catch (IllegalArgumentException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IllegalStateException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            return null;
            }
        public void onCompletion(MediaPlayer mp) {
            // TODO Auto-generated method stub

        }


}



public void onCompletion(MediaPlayer mp)
{

     if(counter%2 == 0)
        {
            played_files++;
            mMediaPlayer1.stop();
            mMediaPlayer1.release();

            mMediaPlayer2.start();


        }
        else
        {
            played_files++;
            mMediaPlayer2.stop();
            mMediaPlayer2.release();

            mMediaPlayer1.start();  

        }
}

public void surfaceChanged(SurfaceHolder holder, int format, int width,
        int height) {
    // TODO Auto-generated method stub

}

public void surfaceCreated(SurfaceHolder holder) {
    // TODO Auto-generated method stub
    try {
        if(counter%2 == 0)
        {
            mMediaPlayer2.prepare();
        }
        else
        {
            mMediaPlayer1.prepare();
        }
    } catch (IllegalStateException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

public void surfaceDestroyed(SurfaceHolder holder) {
    // TODO Auto-generated method stub

}

public void onPrepared(MediaPlayer mp) {
    // TODO Auto-generated method stub
    //if(counter == 1)
        mp.start();

}

}