The game doesn't use mic or webcam. It is not intended.

related issue:
https://gtm.steamproxy.vip/app/366910/discussions/0/2519149567482959322/
This is now the second report i see about something like this. Are you on Mac? I cannot reproduce this on my windows install.

Ill forward it to the community manager, to emphasize it was not a oneoff setup issue.

Interesting thing to note: according to https://steamdb.info/app/366910/history/ the actual build (as in the game's code that's being executed) hasn't changed in ages. I don't know why this issue just now starts to happen.

Reminds me of the Buffpanel discussion 18 months ago (search this forum for "buffpanel").
The two issues are not necessarily related, but Buffpanel does collect data from user PC's, microphone or webcam wasn't mentioned at the time.
The issue was resolved eventually by the developers, but it might be worth making sure that it hasn't come up again, possibly in a different disguise, and possibly limited to macs only?
This is not a complaint or critique, simply an idea which may or may not be applicable to the issue here.

To be honest, that wouldn't make sense to me. Why only Mac then? Buffpanel served a specific purpose, to get information which streamer of the little marketing push you watched. While i agree this is a particular ugly implementation of the concept, it wasn't random data collection. (Edit: and if I recall correctly there was an informational popup)
I was curious though wether the game changed or this just happened, and that's why i posted the link to the steam db update history. It doesn't seem like it. Perhaps when the port was made, there was something configured wrongly, and it just now takes effect with some library updates or so?

As far as i can tell, indicated by time and price and inclusion in game magazines, Daedalic is done with the game. There is no team permanently assigned to work on TLJH, and the port was made by a different team from the original developers.

That said: i alerted the community manager and fowarded this thread. Thanks for the report and input otherwise, if anything else happens/changes/ideas come up, feel free to share, it might help solve it.

No I'm on windows, when I played yesterday it didn't happen, so there's a bit of inconsistency but after reading this I tried again, just pressing the green "Play" button immediately turned on the webcam before the Deadalic splash screen, so this might be a lead as to where to look...
Good luck finding the bug! I love the game so far! :)

On windows too? that's not a good sign.
if it happens again, can you alt+f4 out of the game and send me the log file that should be in <drive>:\Users\<user>\AppData\Local\tljh\Saved\Logs\tljh.log ?

Apparently it switches it open and stay opened every first time launch after a reboot, following launches it switches it on then off.

here's the file : https://justpaste.it/7zt1s
(you can ignore or accept the friend request, I wasn't sure how to send you the file)