To get the full benefit out of Chromecast Audio you need a media server; Plex is a reasonable and cheap (or even free) option, it also has a good remote for every platform. Maybe Audirvana could expand to play this role as well, but currently it’s not an option. I’m actually looking into Audirvana for the exact opposite reason; I want to play stuff via an USB DDC/DAC with the best quality possible - but I still want a remote. The MacOS app for Plex isn’t able to use exclusive mode and switch DAC rates, at least not currently.
My only gripe with Plex+CCA is that it doesn’t do gapless FLAC album playback. CCA limit, I suppose, but with certain kinds of music and more concentrated listening it’s a really annoying tiny pause; The beat doesn’t go on…
Grouping works amazingly well, we have five CCA’s at home and can rock the whole house down, or just parts of it and play something else at the same time.
I’ve even used a CCA in a car just to try it out and it worked perfectly until we reached limits of civilization… One travels with me everywhere - with a 4G/wifi router though.
It’s a real shame that Google killed the product, there’s just nothing like it at any price. Even the closest competitors require something like Roon ($$$) and several times more expensive rendererers.
Oh… and the CCA DAC itself isn’t that bad. Only one of our five has an external one connected. $35, €39, whatever… What a steal.