The game is slowing down while playing.

[ItIsMyName]

So, I faced a problem since the first minetus of gameplay. When I play, the game slows down like in slowmotion without lagging or anything like this. And I cannot predict when the slowmotion begins or starts. And the worst part is when I fight enemies in slowmotion sometimes game goes back to normal speed, and so i catch a lot of bullets and it is very annoying. Aslo, in steam it says that I have 8.1 hours of playing, but in the game itself it says 6.4 hours, and no i didn't spend more than 5 minutes total in the game manu.

[Jeff]

The trick is to go into options when you first load up and cycle from fullscreen to windowed and then back to fullscreen. This fixes it for me.