Polara Pat wrote:
Is there more permanent fix to this issue to allow oxx ooo cross fingering?
I did what Gumby said, when I was playing a Sindt D I was using an old Generation body in it.
Ditto my first Killarney, the tube had obviously been chopped at the bottom and surprise! the bell-note was too sharp.
If you have a tube that you know gives a good scale you can put any head on it, as long as the size fits, which there's no guarantee because my various old Generations have a number of slightly different tubing sizes.
The other fix- perhaps not permanent- is to put a bit of tape on Hole 1.
I had to do that on the Susato Low C that I used to have. It was a great player, but for some reason they decided to make Hole 1 too big, which spoiled the crossfingered C natural and also Hole 1's role as a vent for Middle D.
Not on Hole 1, but here on Hole 2 and Hole 5, the way to instantly transform an Equal Temperament whistle into a Just Intonation whistle:

Do that exact thing to Hole 1 and voila! your C natural crossfingering is lovely.