M-Audio Revolution 7.1 Problem

[SharpieFiend]

Perhaps someone here can help me with this... I'm trying to hook up the digital coax output to a A/V reciever, but the output doesn't seem to be active. I've looked in the M-Audio control panel and the Sounds and Audio Devices applet in Control Panel but there isn't an option for it anywhere. I know the input in the receiver works because I connected the DVD player to it.

I'm using the latest version of the Revolution driver and the latest version of XP. Suggestions?