Hmm, thanks, that's an interesting idea... I could get one of these below, hook it up to the existing harness behind the HU, wire the other end to a 3.5mm jack, and connect an mp3 player.
If that setup gives no noise at all, then I guess I could have a bad headunit. I'm still wondering if I should be disconnecting the factory ground wire when connecting the 2nd ground wire, if that'll affect anything. I'm just hesistant to cut into factory wires unless I absolutely have to.
