so i found a guy who had a similar problem:
"So I formatted my PC this weekend. Put on a fresh copy of Windows 7 and all the updates including SP1.
When I went to play Dragon Age Origins all seemed normal until I got to a situation where characters started talking and I couldn't hear the audio. All the background sound works just can't hear when ppl are talking. At some points you can faintly hear them talking other times not at all.
I thought It was the game until I realized even youtube videos and highlight videos on sports sites also yielded no dialogue audio.
I have tried tinkering with my audio settings with no luck. I also downloaded my latest MB sound driver but this had no effect either.
Please help if you have experienced this....."
he solved it like this:
"I found the fix for anyone who happens to run into this exact problem. After another format I went through the process of getting MB updates, installing windows update with SP1, then installing "CCC 11.2 drivers".
All was working good until I installed the 11.2 driver. I realized that within 11.2 instal manager one of the drivers you are installing is for HDMI audio. I installed the entire CCC 11.2 suite which included this HDMI audio driver and the dialogue sound didn't work.
So voila that was the answer. Went to uninstall programs found CCC and clicked change. Uninstalled just the HDMI audio driver within CCC 11.2 and all sound is now good.
Cheers hope this helps someone with the same issue."
------------------------
i tried his solution since our problems are so similar...sadl
y, it didn't work
youtube vids and games with dialogue both still refuse to give me any voice audio
this is driving me a bit nutty