Am I missing something here? I just ordered a Bach Flugelhorn Megatone 3C and I put it in my Jupiter Carnegie XL Series Flugelhorn and it didn't fit. It still plays fantastically though I and I love my tone and range on it. Sorry if this is a dumb question, but are Bach Flugelhorn mouthpieces a different size than other flugelhorn's? Because I really like the mouthpiece and I don't want to return it, but I don't want to have it falling out all the time and ruin it.