Slider control in silverlight

Question

I am using slider control for an audio player in silverlight application. The slider is not moving while audio is playing. The below one is my XAML code . How to get it?

<Slider x:Name="Slider" Grid.Column="0" Grid.Row="1" Grid.ColumnSpan="2" 
  MouseLeftButtonDown="MouseClicked" MouseLeftButtonUp="MouseReleased" 
  ValueChanged="Slider_ValueChanged" Height="30" Width="484"   ></Slider>

Code behind for slider events:

private void Slider_ValueChanged(object sender, RoutedPropertyChangedEventArgs<double> e)
  {
     Audio.Pause();
     Audio.Position = TimeSpan.FromSeconds(Slider.Value);
     Audio.Play();
  }

  private void MouseClicked(object sender, MouseButtonEventArgs e)
  {
     Audio.Pause();
     Audio.Position = TimeSpan.FromSeconds(Slider.Value);
  }

  private void MouseReleased(object sender, MouseButtonEventArgs e)
  {
     Audio.Play();
  }