I noticed that something changed last couple of months.
Before it was very easy for any familymembers to play music from spotify and just press output to Volumio - unit.
Now it´s almost impossible to do that - it took me a long time to uninstall both apps several times.
Often in the spotify app, it looks like the song is playing in volumio unit but nothing happens even after new installations etc.
Spotify integration is driving me nuts. It is just not stable.
Reinstalling the Spotify plugin has almost become a daily routine by now. The interface in Volumio is just not up to standard spotify. But playing spotify from Spotify just does not work.
I’ve had similar issues with my RPi 4 running Volumio 3.779. I’ve found downgrading to Spotify 4.0.3 has fix most of the issues. For example, I can play a large, multi-hour playlist with out issues. I’d suggest giving it a try. Good Luck.