Concerning condensation and buzzing, do you warm the mouthpiece up before playing? As a recorder player I know this is an important thing to do to avoid condensation building up and causing a muffled sound. On a clarinet it could be causing the buzzing sound I get after playing for a while. The way I see it, moisture builds up between the mpc and reed (both plastic) and with nowhere to go it sits there and affects the sound. It may be more of an issue if, like me, you use a synthetic reed. Might warming the mpc/ reed up before playing help?