MacBook as airplay device

I typically stream via airplay currently using LMS to my airport express. Works fine. MacOS Monterey introduced the MacBook to be an airstream receiver. The same MacBook is my LMS.

Using the iPad to use the web player it sees the MacBook as the receiver but the song doesn’t start to play and nothing heard. Appreciate this is a new thing for MAcOS but wondered if there is anything preventing it working? Is it because LMS is the server on the same Mac?

It’s not a situation I use that often so I’m not too fussed, but wondered if people experience the same.

Thanks