Dead Spot on Fender Jazz Neck

Went to my local purveyor of dreams a couple of days ago to try out some
fretless Fender jazz basses, both American and "other" (Mexican?). As
someone here recently said, I found no significant difference between the
foreign and domestic ones. But, one of the American basses had a distinctly
dull range of notes at the 4th, 5th and 6th positions on the G string. I was
playing scales pretty fast when I noticed the problem, so not being an
experienced fretless player, I figured it was my fingers causing the
problem. I paid close attention to how I was pressing the string in that
range, but the problem persisted. Just a dull thud, with little or no
sustain. All other notes on that string sounded fine, and all other strings
were OK. It was strung with flat wounds.

What would cause this? The store's got a great luthier who will adjust setup
at no charge for new instruments, but still...I wonder about getting a
lemon.


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