I have a cheap alto(G4M),and while it's a good horn and plays well, it has the maddening habit of just not sounding G, in both registers. I will be playing and the G will just not sound.I then play G and the blasted note speaks ok. It's driving me crazy, and of course the last thing I will do is PAY anyone to help me.I have searched and tried the pulling thin paper test,but cannot find a leak.What the hell is going on?