Razer Cortex - Makes Dirt Rally 2.0 Stutter / Flicker

Hey all, I've recently installed Cortex on my 2019 RB 15 Advanced, BIOS v1.05. When I launched DIRT Rally 2.0 for the first time, using the Cortex menu, the game doesn't play smoothly. Its plugged into a 2K 75hz monitor and still records 75 FPS which mid-game but the image stutters and flickers. I had FPS tracking switched on recording average and highest FPS and also the option checked to post FPS results to desktop when closing the game. I had to right-click and close Cortex and Synapse mid-game which resolved the flickering. Any advise or help with this please?