I bought a Sonos Play 1 and Spotify often has a lot of problems to list Sonos under available devices. Sometimes it tries to connect and then nothing, sometimes you cannot see device listed.
I tried reinstall App, it works a few the same problem. I rebooted router, Sonos Play 1, Android device.
Firmware and Spotify app are updated to the latest version.
Spotify SONOS app works flawlessy, i noted that after have played with Sonos app, Spotify comes back to see the device.
I don't understand why this issue is present since months and there's no fix for this, i pay premium app and i would like to have PREMIUM support, otherwise i will be forced to switch to another music service.