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I bought a AVH-P6400 in-dash deck from my buddy right out of his car and it was working. I took it to an audio shop so they could install it, and they did but they couldnt get the Inputs to work right becasue they didnt know how to program the AUX of the HU, i figured that out later. So i was able to play the radio through my system, but Now, I cant get the Inputs to work right, I connected it from my cd-player RCA-REAR-Outputs into the Audio Inputs but nothing comes out, and when i tried to connect the Subs to the Subs out all the amps and subs do is beat like a heart beat and it looks like its shorting out.. And i watch the meters of the amp and they go off the charts on and off, boom, boom, its wierd.. .Does Anyone have ANY idea's about either problem?