No sound, black screen from other users

I used to have a working meet.jit.si in Chrome, but not anymore.
I get black screens and no sound from other users.
I see myself, get the test sound output ok, I see the small “led” display so I know Jitsi receives sound from me.
I see that other people are talking (blue icon), but I don’t see/hear them, nor can they see/hear me.

I checked in incognito mod,
I checked with all extensions disabled ,
I checked in Firefox too,
I checked after a reboot,
to no avail.

With my android phone and the Jitsi app on the same wifi, I can see/hear the others, but not me.
I tested in another room with no success.

What could be the explanation? What else could I do to investigate.