The first t00t is a summary and a paper, probably about the actual project appears in the replies…
I love this kind of idea but have no chance of getting to do it myself, but maybe it will be of interest to someone else.
BTW I thoroughly recommend following the HomeLab and HomeAssistant tags on Mastodon. Especially for anyone who wants to get off the surveillance platforms.
If I understand right you can make a simple automation that runs every X mins only setting the volume of a Mediaplayer playing a song/sound repeatedly. You probably have a CPU or ram usage sensor that can be used to calculate the volume. Does this simple approach works for you?