public void HintBeginPreload()
{
if(sound == null)
{
sound = new SoundEffectInstance(device.Root);
preloading.Add(this);
sound.mediaElement.DownloadProgressChanged += (o, e) => CheckFinishedDownload();
sound.mediaElement.MediaFailed += (o, e) => { downloadFailed = true; DonePreloading(); };
sound.SetSourceForSong(uri);
CheckFinishedDownload(); // just in case :)
}
}