可以使用以下代码播放后台音频：

1. 在AndroidManifest.xml中添加以下权限：

2. 创建一个后台服务，在服务中使用MediaPlayer来播放音频。

public class BackgroundSoundService extends Service { private static final String TAG = null; MediaPlayer player;

public IBinder onBind(Intent arg0) {

  return null;

}

@Override public void onCreate() { super.onCreate(); player = MediaPlayer.create(this, R.raw.yoursoundfile); player.setLooping(true); player.setVolume(100,100);

} public int onStartCommand(Intent intent, int flags, int startId) { player.start(); return startId; } public IBinder onUnBind(Intent arg0) { // TODO Auto-generated method stub return null; }

public void onStop() { player.stop(); player.release(); }

public void onPause() { player.stop(); player.release(); }

@Override public void onDestroy() { player.stop(); player.release(); }

@Override public void onLowMemory() {

} }

3. 在Android的AlarmManager的回调方法中启动该服务。

public class AlarmReceiver extends BroadcastReceiver {

@Override public void onReceive(Context context, Intent intent) { Intent service1 = new Intent(context, BackgroundSoundService.class); context.startService(service1); }

}