No, it's not cause of the game running. You can test it while running any 2-3 programs, just alt tab so the freePIE will be 3rd or 4th in alt tab order and monitor it with Vjoy monitor and u will see. And what is your OS? WIN11 right? Same problem here on WIN11 and I can't seem to find a solution. Maybe, just maybe, turning HPET off will help.