I having some kind of grounding problems on one of my basses. I'm using EMG J-style pickups and have it wired exactly like the instructions say except for the input jack. I'm using the kind of jack shown in the attached picture. It has three little protrusions on the back. Right now I have the hot wire going to one and the two ground wires (from battery and pots) going to another. The third is unused. It work like this but I get terrible hum that goes away when I touch the end of my bass cable. It gets louder when I touch the knobs. Any ideas? I have no idea how this style of jack is supposed to be wired. EMG pickups are dead quite so I know it's something I've done wrong. Please Help!!