Hi guys/gals. I have recently picked up my first fretless bass. It's a Kapok 5 string. I noticed that the B and E strings weren't as loud as the rest, so I had a new preamp put in, but now the B is still softer than the rest. Could this be a result of the pick ups? Do I need to change out the pick ups? I just had the preamp put in, the control cavity shielded, and a locking input jack installed. I don't have a lot of experience with the electronics of my basses, I have a "guy" who takes care of all of that for me at a local music store. It's not an active bass if that makes any difference. Thanks in advance for any information you can offer.