From time to time I get a buzz when playing.... I'm not talking from my lips, but I mean from the trumpet itself. It reminds me a lot of when you play a certain note on the trumpet and it causes some object in the room to resonate. Except that it happens on quite a few notes in the middle register. It started happening when I switched to my Bach 5B mouthpiece. It was fine today, but if it starts happening again, is there any quick fix? Additionally, manipulation of the 1st valve slide bothers me. Maybe it's because I'm mildly autistic (causes difficulties in coordination) but I have a hard time pulling the slides with absolute ease so that it does not interfere with my playing to some extent. It is worst on the high A (top of the staff), where more effort is required to play it than other notes like F and low E. The problem seems to be more getting the slide back IN, as it sometimes will not go back in all the way, and so I have to force the last little bit of slide in. Any advice on getting it to "spring" back more perfectly? I admit I haven't greased it as much as I should, but I did so last week, and I do put oil on it fairly regularly, too. Thanks.