I've noticed something weird on my '72 reissue tele. I tune the g string in fine, and it stays in tune, but it's out of tune from the 2nd up to about the 7th fret. About a quarter tone out. By the time I get up the 12th it's about right again. Only that one string. Any ideas? Been playing 15 years and never had anything like this before, and not like it's a cheapo guitar either.