Roku express 4k IR remotes stopped working

Full disclosure, I posted this issue on a Reddit too.

This weekend, the remote to this device (Model 3940EU2) stopped working and the backup didn’t work either. I confirmed the IR light was flashing and the phone app worked. I initially put it down to the IR receiver being kaput. I’m using the original remote (RC-ALIR)

Plan A was to get a voice remote but they’re scarce at the moment. None available on Amazon, even.

I noted there was a firmware update on 12 September, right before the issue began. I’m now on v 14.6.

I accessed the ‘secret menu’ where I saw some really interesting results (see pic).

Looks to me like the remote is working, but the box has “forgotten” what the buttons mean. Is that right?! If so, is this a known issue and/or is there a known fix beyond either being patient or trying a factory reset?

Thanks.