Only try to reset narrator's delivery to normal if it isn't already normal. I'm making this change mostly because I got a debug assertion failure (which I can't understand or reproduce) as a result of setting the delivery to normal, and I'm thinking I might at least reduce the likelihood of it happening again by not setting the delivery unless necessary.
Only try to reset narrator's delivery to normal if it isn't already normal. I'm making this change mostly because I got a debug assertion failure (which I can't understand or reproduce) as a result of setting the delivery to normal, and I'm thinking I might at least reduce the likelihood of it happening again by not setting the delivery unless necessary.

sillsdev/Glyssen,sillsdev/Glyssen