i have two guitars and two amp
both of them have a buzz problem from10-15 fret first string(with amp)which lower its sustain and sound bad,
but when i play without an amp they have the same sustain as the other frets and sound normal.
what may be my problem?
P.S. it happens with both of my amps

i want to add this for your criteria
i didn´t happened to them before(when i bought them)
What amps and guitars do you have?
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Quote by utsapp89
^I'd let a pro look at it. Once you get into the technicalities of screws...well, it's just a place you don't want to be, friend.