I've got a Dell Optiplex GX620 that will not produce any sound. There are a nice set of external speakers hooked up to it and I verified that they work perfectly - I plugged them into my laptop & they work fine. I uninstalled & reinstalled the drivers multiple times, no dice. Anything I'm missing? I'm looking at buying one of these: http://www.amazon.com/Channel-Exter...8&s=musical-instruments&qid=1269280916&sr=8-3 or should I go with a more traditional PCI interface? Any experience with those USB devices? Thanks!