I have been playing the sandstorm beta 2 for about 3 hours, and it allready happened twice that my mouse and keyboard suddenly don't work ingame anymore. I can't move or look around, neither enter the pause menu using esc. The game hasn't crashed because you can still see foliage movement, moving teammates and enemys. The only way I found to "fix" this problem is closing the game with ALT+F4. I didn't find a way to reproduce this bug so far.
I use the Logitech G502 mouse and the Logitech G610 MX Red´on Windows 10.