In case anyone is using this, I've added in some code changes and small bug fixes. Nothing major, but there is a new version built with these changes. Just delete the old binary and replace with the new one.
I'm running it, though it hasn't fixed my issues completely. I suspect some of them were the sound card, some were the receiver, and some the wireless headphones. Haven't spent enough time to identify which this helps.
I notice that I have problems with HDMI audio needing around 1 second before it picks up and plays on my 970 that I never noticed on ATI or Intel HDMI connections. I wonder if it's just a characteristic of nVidia hardware.
I've never used HDMI out from my graphics card so I dont know if that is normal. Does this utility help at all in your situation? I know it's not ideal but it works. I leave it running all the time on my system and it seems fine.