Why am I getting bad ground noise from my car stereo, when I wasn't before?

[tooshady_420]

I had 2 amps running for a while now and wanted to add a third. When i hooked up my third amp I didn't get any power, so i switched the power and remote wire with one of the others. Then amp still didn't turn on,but the other 2 I had been running would still turn on. Then after I hooked the two back the way it was before I got a very bad and loud interference that sounded like ground noise, but you could also hear the door chime coming through the speakers, because I have a 2001 and newer GM that requires one of those $40 harnesses with it's own speaker for the alerts. If you know a lot about hooking up car stereos than you know what I mean.
I also regrounded my amps too.