The notes on the Bell key cluster of my Bauhaus Walstein alto sax stopped playing yesterday - mainly the B and Bb. I could see that the low B bell key was rubbing up against the RH post of the bell key guard and you will see from the photo that the gap on the LH side is much wider (see first image). I thought that this was the main cause but, couldn't find a way to move it away, and I have no idea how it came to be unaligned (assuming it was like that when I bought it a year ago). Rewind to an hour previously: I had adjusted the screw on the post above the G# key, but about 1 ½ turns, to bring the black "stop" higher (see 2nd image). I did this because I had been having problems getting G# to sound cleanly when dropping from 4 or 5 note intervals and (erroneously - I'm very new to how the Sax works) thought that raising the stopper might allow the G# key to rise and give a cleaner sound. (Yep, "fools rush in..."etc). After an hour of getting nowhere with the key guard, I remembered what I had done to the screw above the G# key and put it back to where it was originally. Hey presto, all keys played perfectly. I have 2 questions (well, 3 but, "Am I an idiot or what?" will need to remain rhetorical, please.) 1. The B bell key is still rubbing against the post although it plays. Does anyone know how to fix it - and if I should? 2. What does that screw on the "stopper" do, as it doesn't seem to be attached to anything other than the "stop" itself. I can't see how it's affecting the bell keys. This is more for my own information, and so that I will be sure to leave it alone in the future. Thanks for any suggestions.