Thanks. I hadn't tried the 12th fret harmonic, I just noticed that the octave on the next string up didn't sound right and some other notes on the g string (teehee!). Yeah, seems to affect the g more than any others. Maybe the bridge is a bit skewiff or something? I'll take it back to the shop for them to look at it before I start fiddling around myself though I think. Don't want to go doing something drastic by accident.