@dantezote it was 8.01 on a Pi4. I cant remember the exact option as Ive recently moved house and the Pi4 is still in a box somewhere.
Just read the link Zing mentioned - that is just crazy that 8.1 is worse for PSX emu than 8.01 (due to the emu - not Recalbox). I will need to tell my mates not to upgrade, as they mostly play PSX & Dreamcast games on their setup.