VLC player: Jerky audio over spdif

[silbeej]

When i set audio output to SPDIF on VLC player, the audio is very jerky, or kind of a skipping sound like on a cd player with a scratched disk. it plays a bit over and over again, then switches to the next sequence. Kind of like put put put put put pow pow pow pow, but with the sound that should be playing at the beginning of every change. any thoughts or settings? I have a sony receiver attached to my custom pc via coax.