I have a Lakland Skyline Jerry Scheff, and on the back of the neck behind the 5th fret is a "rough spot", about the size of a quarter. It is a little darker than the rest of the wood, and looks as if perhaps the satin neck finish wouldn't stick there. It feels different from the rest of the neck, a little rougher. Not so bad, but mildly noticeable. Is there something I can do to smooth this out?