OBS Studio Virtual Cam - Virtual Audio Cable

Hi there,
since OBS Studio 26.x could be installed (tested under ZorinOS 15.3 Ultimate)
via repo

https://launchpad.net/~obsproject/+archive/ubuntu/obs-studio

there is no longer need to add a Virtual Cam via v4l2sink plugin
https://github.com/CatxFish/obs-v4l2sink

also see
https://ubuntuhandbook.org/index.php/2020/09/obs-studio-26-0-released-ubuntu-ppa/

Never the less this is only the half of the way!

In times of homeschooling / hometeaching it is sometimes nescessary that you can use small videos or podcasts during a jitsi-meet or bigbluebutton session as well.

For that purpose it is nescessary that beneath your virtual webcam via OBS Studio the clear sound of the video do not come via a microphone but more over the virtual audio cable (virtual microphone)

Does anyone have a good and working tutorial / videoguide that could be used to learn how to build that under zorinos?

Thanks community