I've been having this same problem as long as I've had my Sonos Speakers (2 years with 2x Play:1)
I can play Spotify thru the Sonos app but not via Windows Desktop App or iOS App.
I used to be able to fix it by turning off the Sonos speakers and turning them on again. This doesn't work with the latest release of Sonos and Spotify.
It's a really annoying bug - enough to turn me off buying more Sonos products or "smart" speakers".
Here's what I think is happening -
Spotify updates their apps, on Windows, and IOS. This breaks the Spotify -> Sonos functionality. Sonos updates its own apps to fix it, it works for a while, then Spotify updates their apps again, and it all breaks again. I've noticed that spotify updates its apps very frequently. Sonos updates its software much less frequently.
This is why the "internet of things" will fail and fail hard.
Individual companies, doing their own thing, not talking to each other, releasing buggy code.
I have found that starting Spotify on a MacOS device (like a Macbook Pro laptop) will show the Sonos speakers under devices. If you play music thru the MacOS device to this Sonos device, Spotify on the other platforms (Windows and IOS) will start to recognise the speakers again.
Hope this helps anyone with this issue.
I also hope Sonos fixes this issue properly soon. Their speakers are way too expensive for this to be have been an issue for soooo long.
Thanks posting here in the Community! We'll gladly help you out.
This issue should be resolved now. If you're still experiencing this, could you perform a clean reinstall of the Spotify app? Make sure to reboot your Windows/iOS device, your Sonos speaker an your Wi-Fi router afterwards. It's a good idea to also remove the access of the Sonos app to your Spotify account using the steps on this page and then reconnect them again. That should do the trick.
If the issue persists, could you let us know the make and model of your devices, your OS and Spotify version?
Hope you find this useful. Keep us posted how you get on.
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“Music is a language that doesn’t speak in particular words. It speaks in emotions, and if it’s in the bones, it’s in the bones.” - Keith Richards
If you're still experiencing this, could you perform a clean reinstall of the Spotify app? Make sure to reboot your Windows/iOS device, your Sonos speaker an your Wi-Fi router afterwards. It's a good idea to also remove the access of the Sonos app to your Spotify account using the steps on this page and then reconnect them again. That should do the trick.
No trick done! Very annoying!
This started happening to me during this week (has otherwise been working flawlessly since initial setup almost a year ago).
After reluctantly performing all the the actions asked for above, the Spotify app still does not connect to any of the Sonos speakers.
Devices: 4 pieces of the Sonos/IKEA "Symfonisk"
Phone: Oneplus 7t, running Android 10.0.9
Spotify: v126.96.36.1996, supposedly the latest version (fresh from Play store)