I bought a 1957 12m a couple weeks back and I LOVE this horn. It's just..great. Anyway, I'v noticed when I get to A2 (above the staff) the sound gets very airy and kind of nasty. This is consistent from A2 up to C3. I noticed that if I press the octave on the neck down, it easily brings the note back to life. This is sort of a difficult problem to describe through text so if I left any important info out please comment.