Frame pacing problems - stutters

[Etronax]

Hi, Etronax here.

I seem to be having similar issues. Except that I can see spikes in the framegraph. White and red line spiking when the game stutters. Happens once every couple of seconds. Oddly enough it appears completely randomly. Mostly I can see it even in the main menu. But just a while ago I thought I had fixed it when the game ran completely smooth for almost five minutes straight.
But here's the really weird part: this only happens when launching the game through steam. SOMA_NoSteam.exe works perfectly fine.