I`m a woodwind doubler and I`m playing English horn (among others) for a musical. On the E key (right hand middle finger) there`s a small vent hole in the middle of the key which is at the top of the offset touchpiece. I broke my middle finger several years ago and it`s just crooked enough that when I play a C#, I think I`m coming off that vent. Developing more flexibility would be my fix if I had more time, but I have days not months.
The question: what is the function of this little vent hole and would I create any tuning or response problems if I filled it in with wax?
Any advice would be appreciated,

Peter

I wouldn`t touch the EH with anything. I would perhaps just work on sluring the notes you were talking about and start building up that flexibility.