Fret buzz fix?

[Dragzole]

My C string is buzzing at the 12th fret. This is extremely annoying because its the only buzzing spot on the fretboard, and i can't seem to isolate the fret its buzzing against. I've tried raising the action and I have to raise it to very uncomfortable levels for the buzzing to stop, so i think the fret its buzzing against is closer to the nut. I've heard you can sand down the fret or do a truss rod adjustment. Help please!

 

[pfox14]

If the string is buzzing at the 12th fret, than the 13th fret is probably a little high. You can sand or file that spot but be sure to tape up all the surrounding areas of the fingerboard so you don't damage anything else. I like to mark the spot that needs filing with a Black Sharpie, so when the ink disappears from filing, I know I removed material in the right spot.