nah. it wasnt this bug. i couldnt even use ESC after switchin the weapon and after the next round was started.
Can explain more precisely how the bug happens?
hmm. not really. sorry. didnt noticed it at this time, thought it is normal

i got something diffrent now:
we played a map FFA, then a voted passed to TDM(dunno how it is exactly called) and then there is the screen where is written "Waiting for players". When i scrolled the wheel-mouse-button down i couldnt use ESC, when i scrolled up, ESC worked.
The wheel-mouse-button is bind to change the weapons.