Another Nvidia HDMI audio issue

Greetings. This is a message I posted elsewhere but thought this forum to valuable a resource to pass up.

First, some system particulars:

Nvidia GTS 250 (Sparkle 1024)
i5-750
4 Gb ram
Win 7 64b
Asus P7H55D-M EVO

Everything is working pretty well with the exception of no audio over HDMI to my Pioneer HDTV. The optcal spdif as well as the front and rear audio jacks all work normally.

In addition to talking to Sparkle, Nvidia and Asus tech support, I have tried the following:

- reinstalled most drivers and even tried beta versions.
- tried HDMI and spdif setting for mobo bios.
- checked HDMI cable and monitor (tv) with other sources.
- checked mobo spdif to VGA cable (yes I installed it)
- tried a second new Nvidia GTS 250
- reinstallled OS
- tried every combination of settings in Win audio panel (enable, disable, default, HDMI, digital etc.)
- spent 25-30 hours reading forums, tech info etc.
- rigged a cable to test mobo spdif header, checked good (in spdif mode unable to check HDMI output)
- tried a second monitor
- checked all Realtek panel settings.
- checked Nvidia panel, audio enabled
- and lots of other stuff.

I am now waiting for a replacement mobo as Asus suggested the audio chip may be bad. I have my doubts but I guess it is possible. Besides, it is about all that is left to try.

I have read of some people having issues with Nvidia cards and HDMI audio but most seem to be fixed with the usual suggestions. However, I have run accross a few who seem to have given up. I would try an ATI card with onboard audio vs this pass thru setup but I really prefer to have an Nvidia card because of FSX considerations.

Yeah, I know I could just use spdif to my AV receiver but that is too easy and I don't want to have to fire it up all the time. HDMI audio is supposed to work. Just a heads up to everyone and of course if you have a suggestion, I am all ears.