Hi, @Davidsaysthis issue is still with the developers, we apologise for the inconvenience.
It would be useful for us if we could get your DxDiag file, you can see how in the link below.
https://support.sega.com/hc/en-gb/articles/9997195057553-How-to-find-my-system-DxDiag-system
Also, some players have noted that after bringing their render scale slider down to 75% (in preferences) the stuttering stops.