As recommended, I wired my equalizer directly to my battery (not through any factory wires or existing wires I had run) to get rid of the feedback I was hearing through the speakers. The feedback just got worse though. A lot worse. So I unplugged the eq.. I think it's just really low quality and was a mistake to buy.
So, I'm thinking I'll get a higher end head unit, since that was the end goal anyway, unless any one knows of a different equalizer I should get. If I upgrade the head unit, I'm thinking I'll go with the Pioneer DEH-P8600MP. It has a 13-band equalizer, with slope, plus auto time correction and equalization. My friend has it in his Camry and it is incredible.