my app runs fine in the emulator but not in the real device
<p>my app runs fine in the emulator but not in the real device,, i have an application with to many buttons with sound here is the sample code, , my application stops in the real device when it goes to that area of code, ,</p>

<p>`public class Lesson_a extends Activity implements OnClickListener {</p>

<pre><code>MediaPlayer a, a_sound;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.lesson_a);

    a = MediaPlayer.create(this, R.raw.a);

    a_sound = MediaPlayer.create(this, R.raw.a_sound);

    View  a = (View) findViewById(R.id.imageButton_a);
    a.setOnClickListener((OnClickListener)this);

    View a_sound = findViewById(R.id.imageButton_ah);
    a_sound.setOnClickListener((OnClickListener)this);

    Button nxt = (Button) findViewById(R.id.btn_nxt);
    nxt.setOnClickListener((OnClickListener)this);

    Button bck = (Button) findViewById(R.id.back_a);
    bck.setOnClickListener((OnClickListener)this);


}

public void onClick(View v) {
// TODO Auto-generated method stub
    switch(v.getId()){

    case R.id.imageButton_a:
        a.start();
        break;

    case R.id.imageButton_ah:
        a_sound.start();
        break;

    case R.id.btn_nxt:
        Intent ne = new Intent(this, Example_a.class);
        startActivity(ne);
        break;

    case R.id.back_a:
        Intent be = new Intent(this, Vowels.class);
        startActivity(be);
        break;

    }
</code></pre>

<p>}</p>

<pre><code>//@Override
protected void onPause() {
    // TODO Auto-generated method stub
    super.onPause();
    a.release();
    a_sound.release();
}
</code></pre>

<p>}
`</p>
