Dell Latitude 5410: Keyboard/mouse issues

[ancan]

I'm using the Latitude 5510 Monterey EFI posted here for Ventura on a 5410, and everything works fine except some really strange keyboard/mouse issues. While typing normally I see nothing not normal, but when I hold down a key it causes "glitches" in the mouse, with cursor jumping around and ghost clicks. It makes it unusable because you often need to hold down a key, like navigating with cursor keys. Anyone have any ideas what can cause this?