I went straight to the battery and used the grounding point by the battery and I have noise from both places.
Im thinking it is the RCAs causing this. Makes me a lil frustrated, but I have been driving around for 2 weeks with NO music as I was installing everything, so ANY music is ok. Even if the alternator noise does kill me :)
Got some better RCAs on order so we shall see :)

 

im going to go straight t battery. i got all my wire in from crutchfield. will install tomorrow if weather is nice. aka above 30

 

Premiere-- an easy check to see if it is your RCA's -- use an MP3 with the 1/8" plug to rca's out and plug directly to the input of the amp and test that way-- that way you can narrow down if it is-- RCA's or a bad ground.. this way you take out the grounding potential loop from the head unit to the amp.

 

Well I have tried eveything possible and I still have CRAZY noise. I completely reconfigured the adapter harness, soldered the connections, and completely removed the factory amp harness out of the adapter. I am running a common ground with the battery, head unit, and amplifier all wired to a distribution block which it connected to BARE metal using a star wash on either side of the terminal and 4 AWG wire. I even wired in a noise filter today and it made NO difference. I am using Knu Koncepts Krystal Kable RCAs which are BEEFY mofos even the installers at work were like "WHOA!! Those things are huge"

The more I try the less the improvement, I am beginning to suspect that it is with the H/U itself and I am probably going to hook up a different radio and see what happens.

I am past the point of pulling my hair out though!!!!!!

If anyone has any suggestions that would be great :) but there isnt much else that I know of!!

 

did you run your wires on the drivers side? the positive battery cable runs down that side. i moved everything to the passenger side and my alternator whine is all gone now.

 

Did you try Dremin's suggestion? Hook up a portable mp3 player directly to the amp. That would take your head unit and RCAs out of the equation. Then it would be your amp or wiring.

 

Is the ground for the HU still connected to the factory harness? You need to have the HU completely isolated from any other ground besides what all the audio is hooked up to.

And sometimes you're right...try a different HU.