I'm hoping this will be an easy one for you guys. I've done hours of research up until this point lol. Quick Info: I installed a Pioneer AVH-X4600BT with my stock Symphony II (non bose) setup. Quick story. I had a shop install my head unit incorrectly. It was producing hiss from the back speakers and a buzz when I turned on my headlights. Well after all the reading I did, I finally got up the courage to hook up the RCA cables so that the hissing will go away. Well I did it, all came out fine. Hissing went away and I found out the shop never grounded period so the hissing went away. My question (which may sound dumb to some, but I'm new at this) involves my sub. It is not working now. I am almost positive on what I need to do, but I wanted to make sure as to not mess anything up. This is the back of my head unit. âTLDR The top two RCA are for the front two speakers, the middle are for the rear and the bottom are for the subwoofer. Well, I never hooked up the sub RCA's. Would I just connect two more white and red RCA cables and connect them to the corresponding RCA wires prior? Edit: Or I do not have it wired correctly for my AMP to come on. Still trying to figure that out.