My HTPC has always had the problem where I have to crank the audio receiver up a lot to get the same audio level output bu my Xbox 360 or Blu Ray player.
I recently upgraded to an ATI 5670, and a Denon AVR-391 so I can use HDMI for audio and video now, and I still have the same problem! My receiver needs to be around -26 for the same volume level my Xbox puts out @ -45.
I run Windows 7 64bit and the same issue is present using WMP, VLC, or Media Portal.
Any ideas? The big issue is when I forget to turn the volume down and switch to XBOX, the xbox start sound almost blows my speakers at that volume.