DeSmuMe Core runahead SD performance

I’m getting really poor performance on steam deck running the latest DeSmuMe core with runahead on Win10. I tried it with all different graphics backends I could but can’t seem to find a solution. When ever I press a button, game and sound start stuttering bad for a second or 2.

The steam deck is more than capable to have runahead enabled for this core, I’m able to play Nintendo switch no problem. My performance overlay shows my GPU and cpu usage only at 15-22% with runahead enabled. I turn it off and game is fine.

Any thoughts?