microphone doesn't work in some applications

[Bleuzen]

Hi, my mic is an Auna 900B and how i already wrote, in some apps it works (examples: OBS, Kazam, Discord) and in some it just records nothing (examples: Systems Sound settings, Audacity, Telegram).

System: Mint 18 Cinnamon (64 bit)

I already reinstalled and i have also tryed it on my laptop (also Mint 18 Cinnamon). Same problem on this device.
Back in Mint 17.3 it worked in all apps and i also tryed it on a Mint 17.3 live session again. No problems in 17.3. This is a new problem in Mint 18.

EDIT:
I found out, that it just resets the audio source to the wrong one everytime, i start a recording in audacity, telegram ...
I have to reset it in pulse audio volume control everytime, i start recording.
But this is not possible with telegram, because i have to hold the recroding button and i cant set the source during this.

EDIT 2:
I GOT IT WORKING!
Setting the default mic in the systems sound settings didn´t work ... but with pulse audio volume control. I just seted my mic as fallback and default there and now it works ... but the bug, that it doesn´t set the default mic in the systems sound is still there.