Game tab's out

[Hveding]

Hey!
I have started to play IL 2 COD a lot these days.. And have found a big problem.. Don't know if others get this but here we go!
When im in-game and play, sometimes if i press "Esc" button the game tabs out, and if i try to go in the game again, it would not do so.. Then im forced to close the game, and then play again.. And this happens almost all the time

Hope someone know why this is happening..
Sorry for my bad English.
-Patrick.