Trying to bind a key to push to talk crashes the game? Any work around?
I reccomend checking out the PC forum section as this key binding on push to talk is a common problem im on xbox so i cant be more helpful sorry. 
If you are encountering issues during the flight, please refer to the known issues list on https://aka.ms/HaloSupportInsider and submit tickets for issues not present.
For general feedback that is not a bug or issue, feel free to use the pinned feedback threads at the top of the Halo Infinite forums
https://www.halowaypoint.com/en-us/forums/29568daf8cd14083bd1b70a810bf3581/topics