I have a tregan shaman bass. A while back i put dimarzio pickups in it and wired it in parallel with one vol knob (it is a pj setup). It has been sounding a bit week since my band got an additional guitarist so i figured i would wire it back to normal so i could take a bit of the j pickup out of the mix to fatten it up. i did not like the tone so i decided to try series wiring. i also figured that i would not be adjusting the volumes between the pickups so i wired the 2 pickups (both are duel coil) and have 4 leads) in series. it sounds great and powerful and i will get to try it in the mix tonight at practice. the trouble is there is a wicked hum/buz now. if i turn the highs down on the amp the hums volume lessens but it is still there. my guess is this is a shielding issue. i have checked all the connections more than once. the noise stops when i touch the strings or the bridge or if i touch the black paint that is on the inside of the control cavity. any ideas? these pickups used to be silent.