HD2600XT on Vista - surround sound stopped working after re-install.

[LostBok]

A few weeks ago, I installed Vista and began experimenting with setting up my HTPC.

Everything seemed to be working fine (1080P, 720P video output and 5.1 surround sound via HDMI).

I'd installed a bit too much "junk", so decided to re-install everything.

Vista will now only output "LR stereo" via the HDMI. When I try to setup speakers, it only gives me "stereo" as an option, none of the surround sound stuff.

I am definitely using the same Catalyst 7.10 drivers for the HD2600XT.

The only difference in how I set this up is that initially is that last time I installed windows with a non-standard (video only) DVI-to-HDMI adapter and then put the proper ATI one in later.

I have tried switching back to that adapter and re-installing the audio drivers. No luck.

The cabling setup is DVI-to-HDMI adapter, then HDMI into the TV (Philips 32PFL9632) and then SPDIF back down into my amp (Sony STR-DG700).

I have tried plugging the HDMI directly into the amp and then forwarding htat up to the TV, I still only get stereo as an option.

Any suggestions?

[LostBok]

I've picked up some new drivers from the Realtek website, hopefully these will be better than the MS drivers, but the really frustrating thing is that this WAS working on the standard MS drivers previously!