How do I enable nForce spdif output?

[WPIDave]

I'm running MythTV on a debian box with an nForce chipset. I've installed the nvsound and nvnet drivers and I get sound just fine on my PC speakers. However, I get nothing from my spdif connector. Perhaps I'm just being dumb, but I can't figure out for the life of me how to enable this output. I know its not MythTV, as I have also tried playing a DVD and an mp3.

Any help would be GREATLY appreciated!

Thanks!

Dave