Ventrilo problems

Hey folks, I just rented a Vent server for my guild in WoW, and am having issues getting my Vent to work properly. I've got it all set up right, and can connect to the server without problems, and in fact when my friends connect to it, they can hear me talking. Problem is, I can't hear them.

I've tinkered with the inputs, the settings, sensitivity, and all sorts of stuff, but still nothing. The only sounds I get are the program's sound effects when someone logs on or off, which I do get just fine.

Anyone experienced this before?

For the record, I have a superbusy network--three computers connected to it (G5 desktop, G4 laptop, the Thinkpad (aka stinkpad) running just for Ventrilo, and an HP laptop connected as well. All are connected via wireless with the exception of the stinkpad running Vent, which is connected via ethernet to my router. I also have my SunRocket VOIP set up before the router.

Not sure if any of that has to do with anything. Just a note--Teamspeak runs fine on the Thinkpad and I never had issues with the input or output sound.