Thanks for your support buddy!

If you think this thread hurts, take a look at these

https://www.diymobileaudio.com/threa....448099/page-7

https://audiosciencereview.com/forum...4#post-1233123

I'm just trying to stay positive

I'm on my third amp, so i doubt it's the problem lol
I think I already tried grounding all rca ports on the headunit together and grounding them to rca cables.

Right now I ran an extra ground cables from the headunit back to the trunk, and grounded it at the same stud where the amp is grounded
I guess as per your suggestion, I can just connect one rca cable out of 4, and ground the outside of that rca cable where it plugs into headunit and into the amp?
It's a bit tricky attaching wires to the outside of the rca cables lead.

So I'll try grounding rca cable to the ground to amp/headunit and see if it changes anything.
Thanks your your suggestion