Alright, I have been playing clarinet for 5 years and this has never happened before. I can't reach my lower register, like whenever I try to play low G, F, and E it goes up to the higher register, and I'm not putting the register key down! What's wrong with my clarinet? It's not a reed problem either, I've tryed it on 10 different reeds, and 3 different level of reeds, 3 1/2, 3, and 2! All of them don't work! Can someone help? Do I need to bring my clarinet in to get fixed?
Take off the top joint and the bottom joint. Cover ALL holes, plug the bottom with your hand and blow in to the top. If you hear something leaking thats the problem.. You should get it repaired. It's happened to my G# key a few times. Also remeber to do the same thing to the bottem.
That happened to me to for a while- at first i thought it was a leak, but i was putting to much pressure on the base of the reed. why that affects it, i dont know. when i stopped doing that, no problem.