What sound systems/ wifi speakers/ audio servers do you run?

Hey Selfhosted! I'm shopping around and looking to piece together a home audio system that supports multi room audio. I'm currently looking and testing a set of speakers I got from AudioEngine that seem to be using the linkplay api.

I'm still piecing together my thinking on this but I'm imagining a system where there is basically a series of mp3/ m3u streams coming off my media server that I can use the audio cast engine to connect to. Alternatively, I think I'll be able to stream directly from my NAS, but I'm not quite sure how/ if any good players exist that will be able to interact with this. I'm still very much in the research phase but have some hardware to play with now.

How are you thinking about home audio systems with regards to self hosting? Any lessons learned or recommendations? Any great tools or kit someone should be checking out?