Hello everyone. I have such a situation. The game goes smoothly, the FPS is excellent, BUT when I press any mouse buttons, the game starts to slow down, go jerkily. If you press any buttons on the keyboard, then there is no such effect.

Who has faced this?

assuming he is the same guy posting the issue on the steam forums, it's SS2.

//looks like he's fixed?

Solved the problem. AMD drivers have such a function - "Anti-Lag (reducing input lag), this function does not always work well, especially with older games.