The Line Out Converter is gone, I have an Alpine head unit now... The hiss is gone completely, but I still get the alternator whine, and only through the amp'd speakers.. so I think it HAS to be the ground. It is currently grounded to the left hand rear seat rail bolt. I sandblasted the bolt so its bare, i sanded the bracket so its bare, and i have a lot of wire wrapped around it. I'm lost.. again.

 

So you did sand the paint on the floor of the vehicle where it will bolt down to? Are you using a ring terminal or are you jst smashing the wire under the bolt?

 

It screws into the frame of the truck, I can see the ground through the hole. It was bare.

I didn't have a ring terminal available, so for now the wire is smashed below the washer.

I feel dumb asking all these questions - I've done a bunch of installs and never had a single problem!

 

Well you should try a ring terminal first....then if it still does it try regrouding it somewhere. Did you run a new ground for the headunit or jst use the one in the wiring harness?

 

wiring harness..

I read about grounding the head unit, but didn't think that was the problem since the whine is only through the speakers on the amp. if the amp is unplugged, no whine.

I'll try a ring terminal.

 

Also seat and seatbelt bolts are NOT very good grounds. The reason is they are hardened steel. Hardened steel has less continuity. But getting a ring terminal defiantly will help!

 

cool, where would you recommend? Drill a hole somewhere?

 

I would def try re-grounding the amp first. You can search around for bolts and whatnot close and try them and as said b4 make sure all paint is sanded off. If you cant find one close, then yes you can drill a whole and secure it into place. I asked about the headunit, bcuz sometimes if the ground for it is bad it will try to ground through the rca's and give you noise.

 

the ground for my amp in my truck is under the passenger seat onto the seat. like this rod. it is bolted in there. it works well for me. you should try that if you didnt already.