Here it a small plug-in for Windows Vista Media Center that enable you to change the sound device used to play back sound in Vista. Since I have both a standard audio cable and a HDMI connection I need to change between them. This can be done with this plug-in through the Media Center with the remote.
The plug-in will look like this in Windows Media Center:
And Inside the plug-in there will be a list of sound devices you can select. In the below example only one device ("Speakers") is shown since it's from a Virtual PC.
AudioManager.zip (587.79 kb) – source