Buzzz problem-Help!

[guithor]

Hi everybody!
I have a problem with Yamaha bass,RBX374 with active electronic,so I hope someone can help.
It is 4-string bass with two Yamaha active humbuckers with open magnet pole pieces.
The bass was "normal" until last few weeks,then come problems with buzzz.
Everything works normaly,passive mode (when active pots are on zero) is ok.
But when active mode is turned ON, pickups works ok ,but when I put the finger on magnet it starts to buzzz,very loud buzzz.Situation is same with both pickups but ONLY on upper coils (neck side) ??.
When I put the left hand on strings buzz stoped.
I know it seems that is no so big problem, but when I accidentaly touch the magnet when I play this is incredible,frustration.
The wiring,pots,shielding...all is ok,the bridge and strings are grounded,pickups also
I was trying all "tricks" I know but now - I`m helpless .

If anybody know how to fix this?

Thanx!!

[newey]

Guithor-

Hello and welcome!

I can't offer much advice. Clearly, somewhere in your active circuit something is contacting something else that it shouldn't be contacting, but beyond that, we would need to know more about your active circuit.

Posting some photos of the innards might help. Sometimes having a few extra sets of eyes look at a problem discloses something awry.

Long-distance troubleshooting over the web is tough. If touching the strings makes it go away it's a grounding issue somewhere though.