Framework 16 "stuck key" behavior at windows password prompt

Every once in a while, I open my FW 16, it resumes from sleep, and the windows password-entry box is filling up with an unknown character.

None of the keys are visibly stuck.
I’ve tried removing and re-seating the keyboard, a couple times, to no effect.
I can use “ctrl-a” + “backspace” to clear the password box, and the problem goes away.

The password box normally has eyeball icon to show the password, but every time this happens, that icon is missing, so I haven’t been able to figure out which key is doing it.

I’ve never seen stuck-repeating-key behavior at any other time - only at the login screen.
It does NOT repro consistently. Maybe 1 time in 10 or 20.

Is anyone else seeing anything like this?
Does anyone have ideas for troubleshooting or fixing it?