WiLL, thanks a LOT for that link. It very quickly solved my problem in one sentence, lol.
"Since the original writing of this section, someone has confirmed that they get odd and horrible feedback from tapping at the speakers and not before the AFBS, so definitely keep that in mind."
That's what I needed to know! Great site though, and a MUST READ for anyone planning of modifying their 5th gen's audio system. Guy really knows what he's talking about.
-Chris