To convert a standard NAS to Sooloos duties (not core) would be pretty straight forward if the NAS already ran a HTTP server. I believe that it's easily within the capabilities of a basic plugin, few custom web pages and minor configuration tweaks.

Meridian owner since 1992
Prime & PSU, Focal Elear headphones, Roon (ROCK 8Gi5 NUC), Explorer 1 & 2, F80. 200/203, various Sonos (via Roon).