I've posted something about this before and I thought that I'd cracked it, but I've just had a practise session for over an hour and that darned top G is at it again. Only on the tenor, the alto is fine. I really have tried pretty much every embouchure combination possible; relaxing the jaw, tightening the grip, standing on one leg etc. I know that it is probably me, but is it just possible that it may be anything to do with the reed/mouthpiece set up (Yamaha 5C and Rico 2.5s)? I rotate 4 reeds at any one time and replace any that seem dodgy. Would a softer or harder reed possibly help or maybe a mouthpiece with a different lay? I am quite happy with the rest of my playing but this is really getting to be a pain. Any advice would be gratefully received.