I've researched this a bit since yesterday and others are saying that it's a bad pot issue (and that the stock pots that came with the OBP-3 are pretty bad quality) and that when the bad pot is replaced, the problem disappears.
I'm going to replace all of the pots first and see if that doesn't resolve my problem before trying a different preamp.
I'm going to replace all of the pots first and see if that doesn't resolve my problem before trying a different preamp.
I went through four different pickups on the FU4 and the whine was always there with the OBP-3.
I would highly recommend the Flexcore, it really opened up the bass tonally and also doesn't have the annoying whine, very quiet even with the treble on full boost.


