I have done practically everything and its just gotten worse!
My system is as follows:
Car is a 1998 Pontiac Grand Prix GTP
Eclipse CD7200 MKII head unit
Aura 5.25 components in the front
Aura 6x9 components in the back
MB Quart PAB5400 5 channel amp
MB Quart DWG-254 DVC 10" sub
I have a 4 gauge power wire ran from the battery back to the amp. The amp grounded to the chassis (sanded the paint down, and cleaned the surface before screwing the ground lug to the chassis). Using Scoshe FX shielded rca's (thinking this may be the problem)
I tried last night running another seperate ground from the radio case to the chassis, and it seems to have made it worse.
So I checked all my chassis grounds, and they were all good and intact, but figured it wouldnt hurt to run a ground wire from the battery terminal straight to the engine block. I did this, got in clicked the key to on and it was even worse then before.
Im a little baffled, as everything I did SHOULD have made it better.
I also have a white noise that is there in between tracks on both CD and USB, and Im sure its there for the radio as well. Blue tooth also. It goes away when you turn the volume to zero, where the alternator whine just keeps humming.
I thought about trying to ground the RCA terminals to the HU chassis itself as well, but they arent directly on the back of the HU like most (they are on leads, so I would have to wrap wire around them and run a short lead back to the HU chassis)
Also, if I disconnect the RCA's at the amp, both noises go away. If that tells you guys anything? Im kind of lost here.