Have had this problem for a few day and spent hours trying all the suggestions found here. Reinstalling apps, reactivating Spotify in Sonos app, checking wireless, rebooting speakers.
I could see the devise from Spotify App on both my Samsung mobile phone devices but when I tried to connect it did nothing. I could connect fine from Sonos app - but not directly from Spotify. After trying many things in the end installinf Spotify on my desktop and connecting immediately worked and then I could also connect from my mobile device.
This is definitely a bug introduced by Spotify. My app on my Android phone was updated November 27th, about the time I noticed Spotify connect won't pick up Sonos system anymore. There haven't been any updates on the Sonos app recently so this one falls on Spotify. Let's all bomb Spotify with emaisl about the issue. I'm very confident Sonos +Spotify is the most used duo for Spotify Connect and that Sonos wouldn't probably sell their system had Spotify not been a music provider for them. It's got to be fixed.
Typical of Sonos to ensure Apple devices work okay - If there's one major gripe on my part, it's that Sonos favour that platform, Android users come a poor second. There's still no voice control from Google Home kit, it's coming in the New Year apparently, but there's no urgency. It makes me wonder about Sonos' future given that there are other more open and innovative alternatives.
Spotify connect has not worked for me for a few days now. I have tried on Android and also Windows desktop. Although both my Sonos devices are shown, it won't play on them. I have tried Spotify Connect against my XBox and that is working fine. So the only problem is Sonos. It only happened after last Spotify update.
Just unplugged system, uninstalled apps from phone, and then one by turned back on modem, and then speakers one by one. Then installed Sonos app, then Spotify, then connected them, and, although I continue to see the SONOS speakers, when I try to connect NOTHING HAPPENS!!! My daughter's iPod connects perfectly of course through the spotify app! I just tried my PC, and nothing - can't even see the SONOS speakers! Come on SONOS.
Re: Can't connect to Sonos players in Spotify Connect