I've had my Lakland DJ5 for 2 years now. It's my favorite of all by basses, sounds great, plays great, but there's a problem in paradise. It hums really really badly. I know when on a jazz bass, when you use a single pickup it'll hum, but when I have BOTH pickups up full, it there's a very loud hum still. Could be a grounding issue, could be a shielding issue... But, how would you guys remedy it?