This game works, when it wants

[Kankkis]

Can somebody tell me why game performance is different sometimes.

Let me explain:

I just booted my computer, launch steam and game(nothing else), going to crosscountry mission, my game is reallysmooth, full 60 fps and really smooth on very low level flight

Next time when i launch game and steam(nothing else), going to crosscountry i got max.40fps and when flying at very low level, game is it not smooth, there is rubberband effect, i mean no stutter but its not smooth like when i got steady 60fps.

Next time it can be good again and so on, this is really weird thing, any other with same problem. I'll use fraps to check fps. Usually first try if i see it's not smooth i quit game and go into windows and restart the game without booting it can be smooth again.

I just start the game on same computer settings, same mission and time, all is same, sometimes it's not working well and sometimes it's smooth and then it's really nice to fly.

Why the game textures is loading after mission starts, really annoying that stutter, i must pan around and wait to get it smooth, first sim when i see something like that. Sometimes in MP it can take very long with that starting stutter.