Thanks for posting this @ripper951. I was getting ready to post the bug myself.
I've noticed it in Battle of Nordvik, I suppose because that's all I've played since it was released Dec 20.
For me sound is also off and it only happens when I first enter a match.
A workaround that works for me is to ALT+TAB to another Windows app (e.g. Chrome) and then go back to the game.
Well, I joined a match and on the very first spawn I could not look up/down/left or right. I tried the ALT-TAB like you suggested but it didn't make any difference for me. Had to completely exit the game again to be able to play.
I was using the Lis character again and I was doing the week 3 Nordvik game.
