Looking back through my correspondence, it doesn't look like I did mention the hum. It must be because I hadn't really nailed down what was causing the hum. JC says that the unit would have been fully tested, and they should have caught the hum. In any case, they're aware now, and he's asking around for other things to try.
Okay, there's no hum if I have nothing hooked up to the amp, but with the amp still hooked up to the speakers. Does that mean anything? I'm thinking I need to borrow back the pre-pro I gave away and make sure that having it hooked up with the balanced connections still creates the hum.
