Hopefully by now mkchromecast [WayBack] works on more Linux versions (and maybe even Mac OS X is better supported [WayBack]), but back then it was only available for Ubuntu 16.10 and up:
Do you want to stream the audio from Rhythmbox, VLC or another Linux app to your TV through Chromecast? Well, we’ve found a nifty little Linux tool that lets you do just that.
Source: How to Send Your Linux Desktop Audio to a Chromecast – OMG! Ubuntu!
The tool is at github: Linux · muammar/mkchromecast Wiki [WayBack]: mkchromecast – Cast macOS, or Linux Audio to your Google Cast Devices
–jeroen
via:
The Wiert Corner - irregular stream of stuff 