T620 plus failing exitbootservices unless USB keyboard is plugged in?

[TurtleRecall]

Hi,

So I've had an HP T620 Plus running Opnsense for a while now (I think since 21.7), but since the upgrade to 22.1.1, after any update it has failed to reboot. When I hook up a monitor (or rather, change input on my TV, as the box is behind the TV), I see an "exitbootservices error 2" and the box just hangs. Can't ssh to it, if I plug in a keyboard at this point I cannot interact with it etc.

I tried restarting by holding power button but same issue, unplugged power entirely, same issue. I then plugged a USB keyboard in and hard rebooted it again and... It worked?

For all subsequent upgrades I've had the same issue and used the same "fix". Literally all I need to do to get it to successfully boot is plug in a keyboard.

Any thoughts on why this might be or what I ought to investigate? Guessing it's something introduced in freebsd 13? Note that this has never been an issue prior to v22.1.1 but is consistently happening now.

Thanks!