I ordered a wiring harness for my pbass. I attached the black wire from my pickup to the black and white wire of the harness, and the white wire to the all white wire. I attached the ground to the bridge. I did look at several wiring diagrams and it looks right. Put it all together and the bass sounds awesome, but the pots don't effect the sound at all. It is like the pickup is attached to the jack. Any ideas what is wrong? Thanks!