I have one of these horns and no, absolutely no tendency to jump the octave on those (or any) notes. So, unless my horn is an anomaly (which I highly doubt), this is not a characteristic of this model. However, it's highly characteristic of ANY horn with leaks. I'd take it to a good tech.
Not sure what's with the other fellow's horn. Maybe those techs he's taken it to missed something.
Not sure what's with the other fellow's horn. Maybe those techs he's taken it to missed something.