According to a press release earlier this week, Roon and Google have come to an agreement to make Chromecast devices Roon-Capable. Take a wander over to https://parttimeaudiophile.com/2018/07/06/roon-expands-its-connected-devices-to-include-chromecast/
and take a look. Also be prepared to read my review of the juiced GCA with hardline ethernet and high end toslink cable compared to a homebuilt Raspberry Pi with similar specs. The results may surprise you.