Ok, so I have 2 basses and neither is particularily expensive. One is a fretted Yamaha bb604, and t'other is a fretless Vintage v940fl. I find that when I turn the treble up, or turn the pickup blend all the way onto one pickup, then I get some background sorta buzzing/fizzing. I was wondering if this was just what happens, or maybe something to do with the lights (tried it with lights out and still buzzed) or maybe it was cause the pickups aren't particularily expensive. Any thoughts on this? I was thinking (since I'm happy with these 2 basses) about upgrading the electronics/preamps in them. The Yamaha has J/J pickups and the Vintage has P/J pickups. Any suggestions? I'm looking for a sorta modern tone, but a versatile one with a warmness to it. Ideas? P.S- Is there anything else I should consider upgrading in my basses that would imporve playability/sounds? Thankyou very much for your help.