Help w/ Tantrum 500.2 signal backfeed?

[ajaye]

I just got a Tantrum 500.2 off ebay and it showed up the other day packed in what may as well have been a brown paper bag. I wanted to test it asap to make sure I didn't get a DOA and had a chance this evening. Now my setup is still incomplete, as of now I just have my ipod running out of the 1/8" jack feeding two 90s era RF Punch amps via RCA splitters (Y-cables). The 160.4 is bridged to my front components HP'd at 80 right now, and the 225.2 is running 2 crappy 6x9s in the rear deck full range. Now I have a truck I use for work every day so this car only gets driven a couple times a week, but since I got everything installed to this point it is DEAD quiet w/ the ipod plugged in and off, and what I would consider a normal amount of noise when the ipod is on, which is also volume dependent, no whine or increase/decrease w/ RPM, I am 99% its just the signal from the ipod itself and the amount its being amplified.

I swapped the Tantrum in place of the 225.2, changed nothing else, and all of a sudden I have HORRIBLE noise from the FRONT components which are fed by the other amp, no noise from the rears that are now fed by the Tantrum. When I pull the RCAs from the other amp and just feed the Tantrum, no noise at all. I then tried to feed the Tantrum from the ipod, then feed the 160.4 from the Tantrum RCA outputs, ditching the Y-cables all together. Noise from the fronts was at least the same, possibly worse.

This one has me a little stumped. Eventually my preamp will be feeding the Tantrum inputs with dedicated LP signal, and the other amp(s) will be fed their own FR signal via their own cables. Do I roll the dice and hope that there won't be a problem when I get to that point, or go through the rigamarole of trying to get my money back?

Here's a pic to get a better idea of what I've got going on. Excuse the mess, work in progress, once I finish the sub/box and figure where the hell to put the preamp, its gonna get cleaned up really nice to show off those sweet ass custom leather covered panels I made to mount the amps on.

[ajaye]

I just figured out that the way I have the 4 channel wired is a two channel mono bridge (only feeding front L+R input in 2 channel and bridged across front and back vs. bridging across both lefts and both rights). Don't know if that could cause my issue, I'm not sure how it would, but I can't reach the tiny wizards that live in my amps and make them work to explain anything.