I have a problem and the explanation might be lengthy so please bear with me.
I have a Warwick Streamer Stage 2 which I bought second hand few years back and it had upgraded Bartolini pickups and preamp. When I first got it, it behaved strangely when using the bass control. It sometimes dropped out and when maxed it made a clicking sound. I took it to a tech and I dont think he looked at it thoroughly. He just said that the pot was not grounded.
I gigged it two weeks ago and it was fine. I went to a band practice last weekend and then it had stopped working. I managed to play it in passive mode and I was looking at it when I came home. The strange loud click is back when I turn the bass control.
I was looking at it this morning. Its the old Bartolini NTMB-918FL which has two parts. The old MEC preamp came with the bass and I am assuming that all pots and controls came stock with the bass.
Diagram is here https://bartolini.net/wp-content/uploads/Docs/Electronics/EQs/ArchiveEQs/NTMB-918fl.pdf
After looking at the diagram and looking at the wires (and its a lot) I am not sure if it has been done correctly originally. I always assumed that the stacked controls were mid and treble and bass was separate but by that diagram I am wrong. Very embarrassing to say that after playing bass for almost 30 years and most of that time with active electronics but not being able to tell the difference between mid and bass lol.
Does this sound like something someone has come across (fault pot maybe) or is this something more complicated? I have changed pickups number of times in guitars but I have never done anything to my basses because of the pre-amps. I noticed in one thread that @ICBM said he deals often with active electronics. Is this something you might have an idea what might be causing it?
https://imgur.com/0oqBvZT This is the pot in question (if that is the problem)