1995 525i Stock radio aftermarket amplifier upgrade

[sleepere34]

Hello guys I recently obtained this 1995 525i and I have been trying to get it back to as close as stock as possible. previous owner had installed a aftermarket Sony head unit along with a unorthodox "oem amplifier delete". somehow the radio still worked as he butchered the OEM harnesses in the back and bridged a few cables and the radio still worked. I went and bought 4 brand new kicker 5 1/4 speakers for the front kick panels and rear deck along with a brand new alpine 5 channel amplifier (4 channel and 1 woofer). the problem I am having at the moment is I am getting this crazy static from both rear speaker channels and also the passenger side. i am using the speakers with the oem harness and I am using the hi low alpine-supplied adapter to bring in the 4 channels from the head unit to be able to output the 5 channels on my amp. has anyone else experienced this when upgrading the amplifier?

my head unit is a c43 unit that I just purchased from some local guys that refurbish units and bring them to new specifications.

I would like to thwart this wicked static I am receiving.

I will provide photos in the next comments of the connectors on both ends of the loop.

[summitp]

You are going to have to check the wiring diagram, if your car originally had a common ground for all speakers, you may have to run new speaker wires to the amp. The Alpine unit would not be designed to use a common ground for inputs

[fo3]

They're trying to use a bmw c43 factory style deck to run a modern amp and speakers. So they have head unit limitations and no pre-outs - you know the usual story when the audio is bad.