The 15th fret could also be too low. Confirm by placing a straightedge on the 15th, but not extending to the 16th. If the straightedge rocks on the 14th, then the 15th is too low.
I use a 6" long stainless ruler to check for high/low frets. By sliding it toward the bridge, any bumping on the end of the ruler indicates a high fret. Rocking is self-explanatory.
In general, buzzing on the first string only is indicative of a fret that is not seated on the end (very common). Sometimes, the fret can be glued down with thin CA, pressing it down with a small block while the glue sets. If that doesn't work, I remove the fret, re-bend it, and reinstall it.
Quote:
|
with no new damage to the top
|
Done correctly, you should experience no damage to the top when ungluing the extension.