Having a really bizarre problem and have scoured for a post about this already but to no avail. The game works fine and all keys are bound etc until I join a team. Be it Aliens or Humans it makes no difference, nothing works except the T and Y chat options. Mouse moving function stops but I can still click 1, 2 and 3 and bring up little menus (in the case of 3, following a player around on screen). Any idea how to fix this? It'd be much appreciated.