Same happens when I close all apps, and stop all active apps.
Discussion
There's a permissions manager app that lets you see what permissions were granted to a sensor.
Do you have apps allowed to access the mic all the time or only while in use?
Yes, same happens when none are allows and only a few are ask every time.
In privacy dashboard > microphone usage, it shows jitsi at times where general microphone access was granted, but jitsi was fully closed and not running in the background.
Yeah that's odd. I know I occasionally get the location icon unexpectedly appear but when I check, I've left an app running. It disappears when I close it.
My gut feel is that you've got a rogue app that's accessing your microphone.
It'd be cool if Graphene told you what was accessing the mic.