If you have fret buzz at 12th fret or higher its common for the problem to be the neck is angled backwards too far.
Thats the problem my tele had.
I put the shim on the headstock side of the neck pocket to angle the neck forward a little.
I put the shim right between the 2 screws that are furthest away from the pickups and fret buzz went away.
HTH
Eric