private void OnSourceRemoved(SourceEventArgs args)
 {
     if (args.Source == installedSource)
     {
         installedSource = null;
     }
 }
 private void InstallDisplay(NowPlayingSource nps)
 {
     if (installedSource == null && nps != null)
     {
         nps.SetSubstituteAudioDisplay(contents);
         installedSource = nps;
     }
 }
        public void Dispose()
        {
            if (installedSource != null)
            {
                installedSource.SetSubstituteAudioDisplay(null);
                installedSource = null;
            }

            contents.Destroy();
            contents.Dispose();
            contents = null;
        }