Program crashes when starting Static media player from another class

view story

http://stackoverflow.com – I have a class which contains a static media-player, but when I try and start the media-player in another activity the program stops working and I cannot see why in my logcat. Here is my first activity, the one from which I am accessing the static media player: public class MainActivity extends Activity { TimerClass t = new TimerClass(); Button start, end, nextclass; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); start = (Button) findViewById(R.id.buttStart); end = (Button) findV (HowTos)