[tinus_hn]

This happens only if the permission is for ‘while using the app’. This permission means that part of the app needs to be visible on screen and if it’s not, the banner will show.

If you change the permission to ‘always’ the banner won’t show.

[lvillani]

That only applies for location access. Even then, you'll see an arrow in the status bar and there's a page in the settings that lets you see which applications are actually accessing your location in the background, and how often.

Mic recording, on the other hand, is always user-initiated and very explicit.