I've been having to use my keyboard frequently to talk on Vox/Range.
It's because both my Vox/Range buttons mapped to my joystick will both transmit on vox, or both will transmit on range. When I go to map controllers, the game recognizes both buttons and one is set up for Vox and the other range. Usually both will cause me to transmit on vox but sometimes it flip flops and both will transmit on range. Then sometimes the problem goes away. Then it comes back, but always in the controller set-up, everything is right.