There isn't one afaik. Just a note that Lemmyverse (and LemmyNSFW) is very vanilla currently and fetish content (especially like this) tend to get downvoted by folks who don't know how to filter out or block specific types of NSFW content in their feeds.
Just try to name your new community (if you start one) smartly so that audiophiles don't get confused 😉
See similar question from a a month or so back in this comm. https://lemmynsfw.com/comment/724836
[Additiona] I have been just putting some of that in the more general !femdom_gifs@lemmynsfw.com , like https://lemmynsfw.com/post/1256212
Yeah I spotted your gifs indeed 😬 I think it could fit into some kind of fetish, like medical or something, I'll have to give it a thought at, some point!
I haven't seen one like that on this instance but maybe another instance has one?
I just did a search here: https://lemmyverse.net/communities?query=sound&nsfw=true
https://lemmyverse.net/communities?query=audio&nsfw=true
And I see this one: https://lemmit.online/c/gonewildaudio
But don't see any posts but that's probably because I am not logged in over in that instance
Also these which are actually on this instance
I don't know how much worse than general nsfw you guys think it is. I don't think it's that bad. Sounding is where you insert something into your urethra. Usually it's a male activity. If you are afraid of penises then maybe don't look it up. Maybe the simple idea of inserting something down there might make you uncomfortable. Also it's the name of medical procedures where a doctor inserts something into the urethra so there's plenty of nurse/doctor imagery if you look it up.