I have a MB CO that recently developed a rattle/buzz tone on the 1 hole draw as well as a new Seydel silver that does the same rattle on the 1 hole blow. On both harps it only occurs if I hit the note kinda hard. Thought maybe the reed was banging the plate (off center) but was not the case when I took it apart to adjust it. Anybody know what's going on and how to fix it ?