Windows 7: Strange sound issue.

OK, I'm stumped.. I'm having some major sound issues that I can't seem to resolve. I'm pretty much at the point of formatting and reinstalling Windows 7, but before I do, thought I could post here in hopes of some alternate suggestions..

I have Windows 7 installed on my HTPC, which runs WMC, with the Media Browser plugin exclusively. The HTPC is connected to my TV via HDMI cable (both sound, and audio) with the default audio playback device set to "Digital Audio (HDMI)". I am using a Harmony remote, with a USB receiver-which, strangely enough may be the issue.

It seems that sometimes when I switch between activities (TV, Video Game, HTPC) on the remote for some reason, I lose sound on the HTPC. I can be watching a movie. Stop it. Use the remote to switch to normal cable TV, or switch the TV off- then sometimes after a few minutes, or hours- sometimes days- I switch back (via remote) to the HTPC, and the sound is gone. What is strange is that when I right click on the speaker icon, and click on "Playback Devices" the "Digital Audio (HDMI)" shows as "Not Plugged In". The HTPC runs 24/7 (still trying to resolve sleep issues as well) So it is not powered down, or rebooted between these sound losses.

Now, here's where things get weird. If I switch back to normal cable TV, then switch back to the HTPC, the sound is back with with the "Digital Audio (HDMI)" icon showing to be the default device again.



Has anyone experienced such a thing? At first I thought it was a driver issue, but now I'm leaning heavily toward the remote itself, or the USB infrared receiver, which came with a generic WMC remote, and seems(?) to work with my Harmony 520. At least when using it to navigate through WMC.

For now I am going to stop using the Harmony, and use the original TV remote to toggle thru the inputs, and try to confirm if the remote is the issue.

Are there any USB settings within Windows, or bios I can check, or configure that may be related to the sound?
Any help will be monumentally appreciated..

Thanks,

Don