Passthrough audio dropping out on receiver (Windows 7)

[Phat J]

Hey everyone,
I need some insight here please.

I have my PC hooked up to my Denon receiver via optical audio out from my ASUS Xonar DS sound card.
The pass through worked perfectly fine on my old XP system, using FFDShow and Media Player Classic Home Cinema.

But now I finally decided to upgrade to Windows 7. When I play back a video with AC3 or DTS, the audio drops out every few seconds, regardless of what player I use (I've tried MPC-HC, VLC, and BSPlayer).
The "digital" light on my receiver flickers on and off when the audio drops.

I cannot figure out what is going on. This does not happen with non-passthrough audio, so it's not a cable or connection issue. I'm using the same files off the same hard drive as before, so it's not an issue with the files.

The only difference I have discovered when putting all my audio settings back in after a fresh re-format, is that I used to just enable the passthrough in FFDShow, and all was well. But when I did this in windows 7, the passthrough wouldn't work at all. The only way I got it to work was in the windows audio settings, where it lists my Xonar DS sound card, and has a passthrough feature there, which I enabled. I never had this setting in XP.

But this is where the dropping audio problems started, so I'm really at a loss here on what to do, besides ditching Windows 7.

I tried deleting all the drivers and reinstalling them, same issue.

Any ideas? Thanks in advance.

[Phat J]

It turns out my computer suffered from hardcore latency. I ran a program called LatencyMon, and it was maxed out to the red on every possible level.
I had no idea where to start with troubleshooting this, so I started with a chipset driver update, and voila! Problems solved.