Audio issues on Mac

Hello, I’ve only been using stream labs for about a week. Still trying to get set up but every time I go to change the audio mix. Or add a new source it seems to cut my microphone and mute the audio in my headphones. I found myself changing one setting and then having to restart the whole application before setting up the next step. Then repeat over again with the reboot. Is it the version I have set up on my Mac? Or is this a common issue with everybody for starting out? Any help would be great thank you!