JL Audio System Noise --- Help!!!
So I have a JL 12w7, 1000/1 amp, 300/4 amp, mids, lows, tweets, JL and stinger RCAs, and a HC600 2nd battery, with a pioneer 5900 HU.
It is all installed into a 98 Honda Civic Hatchback EK.
The sub, 2nd battery, and amps are all in the trunk. I have a separate ground for each amp and 2nd battery. My HU is still using the OEM ground.
I have tried moving the ground for my 4 channel amp to different locations but no matter where i place it, I get ground loop noise. (It's not the whining noise).
I have sanded thru the paint to the metal then grounded and even tried oem screwed locations such as the spare tire screw and the rear seat screw. All no-go.
I bought a multi-meter to help but I am now more confused with what to do with it.
If any of you has any suggestions at all, please share. Thanks!!!
(If you have a similar car - where did you mount your ground?)