private void PlayButton_Click_3(object sender, RoutedEventArgs e)
 {
     if (playButton4.Content.ToString() == "Play")
     {
         Media4.Play(); playButton4.Content = "Pause";
     }
     else
     {
         Media4.Pause(); playButton4.Content = "Play";
     }
 }
 private void RestartButton_Click_3(object sender, RoutedEventArgs e)
 {
     Media4.Stop();
     Media4.Play();
 }
 private void StopButton_Click_3(object sender, RoutedEventArgs e)
 {
     playButton4.Content = "Play";
     Media4.Stop();
 }