I've recycled some of my PC parts into a Linux based HTPC. So far everything is working great except for sound. I'm running OpenSUSE 12.1 x86_64 and XMBC Eden.
I added a Gigabyte GT520 nVidia video card and connect that to my receiver via HDMI. I'm using the nVidia drivers and the HDMI dummy audio device shows up but I've had no luck getting audio out the HDMI port.

I've Googled, but no answers that helped.

Any help would be appreciated.

I'm a fairly advanced Linux user, but HDMI audio is new to me so I'm a n00b on this one.

Thanks

Well, I have made some progress.

Anyone here remember the old days. When the UNIX(Linux) motto was to make small programs that did one thing very well and then combine them for more complex functions?
I see that those days are increasingly over. Like how we went from XMMS where a simple click and you were listening to an MP3 file or M3U list to now we have Amarok and bigger monstrosities that try and do everything at once.
Linux audio has become the same. Linux sound was a nightmare for years. Then we got ALSA and after a little work it became pretty reliable. Now we have ALSA, Pulse, Jack, Phonon, ad nauseaum.

Well this is why HDMI audio on Linux is difficult and why there are dozens of different tricks and howto's to get it all going, none of which work for everyone. Every distro has a different number and colour of audio balls you have to juggle to make this work. It's maddening.

I've gotten it to work manually, but not automatically. And even if I do completely solve it, I'm wondering why I'd post the solution since it would likely help no one but those with the exact same configuration as me. It's ridiculous.

What happened to K.I.S.S. engineering?

OK, so I got it working 99%, though the remaining 1% is a bit of a glitch.

I followed the nVidia HDMI audio how-to (Which I found after a lot of Googling) and by the end I had audio working and figured out my HW device was HW:1,7 so I plugged that into the settings dialog in XBMC and voila.

The caveat is that the system does _not_ like it if two things try and use the audio device at one time.
I cheated in resolving this by pointing the system, and KDE, Pulse, Phonon, etc. to the onboard Intel audio device. This gives me no sound from the OS, but I don't care because I'm using this for XMBC. I'm sure there's a better way to resolve this, but at this point, I'm satisfied with the solution.