I just upgraded from a Galaxy S23 Ultra to a Galaxy Fold 7.
And doing the same thing, i've always done to play music, which is to open the spotify app, click the speaker button to connect to my sonos and then play music through the spotify app. With this new phone after about ten minutes or so the sonos stops playing and the music kicks back to playing on the spotify app on the phone.
I can reconnect it and then ten minutes later, it does the same thing. This last time after I reconnected it by clicking the speaker button in the spotify app I turned off wifi on my phone. Thinking somehow that might do something.. But it didn't, it ended up kicking back to the phone anyways.
I have about a dozen sonos speakers on my network. But I usually only play 3 to 4 at a time, which was the case this time. I have an eero 6 pro wifi mesh setup.
I don't know if this is a spotify issue or a sonos issue but I figured I would ask here first, thanks!