nandohyphen1 the stock implementation recorded no sound for me either. This app did
https://gitlab.com/vijai/screenrecorder/-/releases
Install in Owner, then use the 'plus' icon in Space drawer and push the app to the space, or push it to the desired profile, it has to be installed there.
And install some video player in the profile/space, for testing the results.
In-app audio setting: MIC