Hiss :(

[geowick07 10+ year member]

EDIT: Didnt read this page before i posted...sorry 05AztecRed, but doesn't hurt to reiterate. >>>

your ground should be

actually i think that is your headunit if it happens while the rca's are disconnected. i had to actually ground my h/u to a screw behind the dash to fix that problem. the stock grounds on the wiring harness ****. and is your deck a pioneer? you may need to ground the preouts.

This is also a possibility. I have a Pioneer DEH6800MP, and i had to rerun the ground to a screw behind the cage to remove the hiss. Must be some sort of Pioneer problem, but it is a fairly easy fix.