Hi Y'all! I'm new to this posting thread thingy, so if I'm in the wrong place sorry. Anyway, my problem is this, deep breath! I am in the very lucky position of owning 2 Double basses and a Palatino Upright DB, The problem is my working DB has developed what I can only describe as a Quack or choke note when you fret the A string on the fingerboard and doesn't sound big and round like the rest of the bass, tried new bridge and shaving down fingerboard and hightening action, even tried small peice of rubber in string slot at nut and bridge.I have the same problem with my Palatino bass but it's over the D string, I use a Fishman BP pick-up on both basses. The annoying thing is both basses sound great but as you can imaging this choked string noize is amplified making it sound worse. What's more annoying is the rest of the band don't hear it. I would use my other DB which was my Fathers and sounds great unamplified but it's an old bass and tuning pegs are prone to go out of tune.