Having issues since updates to v40

Hey guys,

Ive asked on discord but not had much luck. Hoping someone here can help.

Was running v38 for months with absolutely no issues. (I only really play PS2 and GameCube games)

I updated to v40 and upon trying to play my first ps2 game it said I was missing BIOS files. I added the missing file and found the game was stuttering really badly. Completely unplayable. This only happens during actual gameplay, navigating menus is fine. The issue is also present with GameCube games.

Any ideas?