No Input Bug

Hey,
since a few days I face a weird problem. From time to time while playing wow (doesn't matter where I am or what i do) my whole Computer doesn't accept input anymore. The game keeps running my character does what he did(keeps walking forwards/backwards) when the game crashed and i cannot tab /alt F4 / Taskmanager, i can't even activate or deativate numbblock in my keybord. Neither can I see my Cursor or use ingame functions like chat or menu. The only thing to stop it is to shut down the computer manually.
I would really appreciate any kind of tipp :D

Greetings