Problems with Audio/Video overlay in Windows 10

Hello,
i recently installed Windows 10 and the "player overlay" shown in the attachment keeps popping up randomly every now and then. It pops up in the front, covers up games, movies or work that i'm doing and i cannot get it away as it has no button to close it.
I would like to completely remove it so it never comes back. Unfortunately i have no idea how the process is called (not that i could find it in the disaster of the Win10 task manager anyway) and haven't found much so far on the internet as my ability to describe it without a picture is somewhat limited.
I hope you can help me to rid myself of this blight. Thank you in advance.

Greetings,
Knolf

PS: Windows version: 1909

Daum Potplayer for Video and MediaMonkey for Audio.

This player overlay thing doesn't appear always. It's completely random. Sometimes it pops up when i start a video on youtube, sometimes in the middle of one, sometimes when the video is paused.

Apparently it has something to do with with the Notification assistent which i cannot deactivate, no matter how often i click the button.
Windows 10 seems to be resetting my choice to deactivate any of it's "services" whenever i close the window.
thanks for trying to help but i cannot tolerate this OS any longer. i'm going back to win7 for entertainment and linux for work as this entire system seems beyond malicious.