Hello, I have a tenor sax that I bought second hand. It's a cannonball and quite a nice model. I've been playing for two and a half years and have never had a problem but a couple days ago I couldn't play anything except a low D. My middle C, A and B squeal uncontrollably. I've checked all the pads, my mouthpiece works by itself as well. I just thought I'd check and see if anyone has any ideas before I take it in to a technician.