So my card is pre-Azalia so the how-to doesn’t help:
I have nothing in aplay -l regarding the gpu, and I can’t find an nvidia-settings knob to turn to try to enable the passthrough. I can boot into windows and it works pretty much out of the box and shows up as audio to output in the control panel. Outputting to the onboard audio SPDIF PCM goes to the back of the board SPDIF port. It might also go to the onboard spdif header passthrough cable, but I wouldn’t be able to tell.
So how can I get pre-Azalia passthrough working on a gtx 285?