I used OBS Studio to create a scene with LiveSplit as an overlay, but, even with no software running besides the game, it still is running slow. I tried other games but they run fine.

Yesterday I submitted my first attempt at Any% and it was rejected. 

Interestingly the reason was that  my game ran slow: "Compared to another run you're 48 seconds on the timer to each of their minutes. " 

I have no idea how to go about fixing it. Assist mode is off.

My computer meets minimum requirements and I get plenty of FPS. I have tried windowed/fullscreen, vsync on/off and having no other programs running. Nothing seems to affect this issue.

I'm looking for suggestions/ideas!