When I first got my Dot, it buzzed at the 5th fret. One of the main issues was that it was set up for a different gauge of string than I was using and the nut was just not done right.
I had the guitar set-up by my Luthier, he changed out the nut and set it up for a specific set of strings that I was using.
Buzz was gone when I got it back and it plays like a dream'
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