Ive installed a fair amount of new HUs in cars but I have never been so increadibly confused until today. I was ripping my 87 325i HU out so I got it all out, i have the premium sound btw, and I popped the fader out and cut the wires. I took the 4 + wires for the speakers from it and hooked them directly to my HU. Then I ran a +12 to the remote for the factory amp, a constant 12 for my HU and then the ignition/switching for my HU. But I can't get Spound to even flicker. All my ground for the speakers are wired together on the HU, wtf are they for the speakers???? What is going on, damn crazy germans