I was, and still am, encountering audio problems. I was tinkering with my IR blaster when (probably unrelated) I lost audio output. I've uninstalled the Hauppage IR program that I had installed prior to losing audio in the unlikley event there was a conflict. I put a previous post out about an audio problem and was advised it could be down to the realtek onboard sound. At that stage the audio problem was effecting all sound output when TV turned on and off. This required a reboot to get audio output back. Since trying to get the blaster to work it is now only effecting MP and I can't get any audio out from Mediaportal, I had not changed any of my video or audio decoders. Since I was having the problem I decided to move to RC3. After reinstalling Mediaportal RC3 I still can't get any audio, it's not just related to playing files or TV, if I click on any element of MP there's normally a recognition click as you switch between views, now nothing. It's as if a "mute" has been turned on. I still get audio in all other applications including Real Player and Powercinema so it looks like this time it really is only an MP issue. any ideas???
I'm also having an EPG problem again (updated EPG problem post) but this is secondary to no audio.

Finally bit the bullit this evening and reinstalled Vista, second time in a month, which is quite tedious. I have audio in MP again! However, still have the problem that if I turn the TV on and off while MP is on I lose audio when TV turned back on. Tomorrow going to be spent sorting EPG out again and trying seperate A/V rather than HDMI, which defeats the object of sourcing a MB with HDMI out.