Bad stutter in vanilla SupCom

I wanted to play the campaigns vanilla (SupCom, not FA yet) before I tried multiplayer or anything to get used to the game, and even on the first mission stutter gets extremely bad. It's not a constant low framerate or anything, so I'm not sure what to do. I googled around a bit but there's nothing too concrete on this issue, especially with modern hardware. Any help is appreciated.

update: I think it's because I'm moving my mouse. It causes an extreme lag spike for a minute, and it does it on Dawn of War as well. Tried disabling steam overlay, does not work.

Windows 10
Ryzen 7 3700X
RTX 2070

Please open the ingame console and type:
d3d_windowscursor

(please report if this helps)

@Uveso This seems to have fixed if for me in FAF. I'll try it out in a proper game tonight.

@Uveso This seems to have worked. Thanks.

@Uveso This seems to have fixed if for me in FAF also. Thanks

Thanks a lot for reporting !

@Uveso Worked for me