From my (limited) understanding you cannot really switch these off inadvertently as they require a couple of actions in order to be switched off. So it would mean one of the pilots switched these off (and they were a few seconds later switched on again but it was too late).

But there was audio, too, and one pilot asked the other "why did you switch these off" and the second one said "I didn't".

Was there are third one in the jump seat?