title: Sync multiple MediaItems
body: <p>I have an application that plays for wmv files at the same time - they are all together controlled by one slider and play/pause/stop buttons.</p>
  
  <p>I am using the code below to control the video via the slider - problem is, that they get out of sync as soon as using the slider two-three times or often. Anybody got an idea on how to fix this?</p>
  
  <pre><code>    private void slider1_DragCompleted(object sender, System.Windows.Controls.Primitives.DragCompletedEventArgs e)
      {
  
          videos[0].Position = TimeSpan.FromSeconds(slider1.Value);
  
          foreach (MediaElement elem in videos)
          {
              elem.Position = videos[0].Position;
              elem.Play();
          }
  </code></pre>