Not sure where to put this, but for those who don’t know music/audio synchronization between multiple Amazon Echos is near. The option is currently grayed out on my alexa app so I’ll have to wait for the update before I can test it. They stated Spotify support is coming.
EDIT - The reason I posted this here is that there should be “Connected Speaker APIs” coming soon as well.
According to this site, my 1st gen Echo’s are up to date with the most recent firmware:
I’m going to chalk it up to my Alexa app on my phone supports configuring multi-room music, but Amazon hasn’t officially released the updated firmware to the first gen units.