I have just bought a Selmer S80 C* mouthpiece for my Bari sax to replace the S80 D, and a Rovner Dark lig to replace my BG. (I am still trying to hit that elusive F' and thought this may help) On first trial, I noticed that the sax resonates or buzzes when I play D and Eb with the octave key, and it feels muffled. I put the old mpc/lig on to see if that was always there, and it's nothing like as obvious, but it might be there. Is this something that I will learn to play better, and so lose the buzzing? I only had time for a few minutes trial today. I've only just had the Bari serviced, so my gut instinct is that it is the mpc/lig rather than the sax. Any thoughts or suggestions?