Chromecast audio with Alexa multiroom audio

Okay, I’m not sure anyone has tackled this before. I can’t seem to find anything on the internet about it. Maybe I’m not using the right words to describe what I want to do.

I have a few Chromecast audios, a home mini, a few echo dots, and an echo home.

Both Google and Alexa now supports whole home audio, but how can I bridge the gap? I’d like to simultaneously stream a music source or streaming service to both Google Chromecast AND Amazon echo. Is there anything that would do that? Possible an app I’m unaware of.

I’ve been trying to find an elegant solution, but so far I’m coming up empty.

Thanks for the help!

I seriously doubt you’ll be able to get synchronized playback across the two platforms.

I went with Sonos several years back when I had more money and none of the “smart speakers” existed. Have never regretted it.