We had a power interruption, following which my router rebooted normally. I was able to do all normal connections to the internet from laptops, phones, etc. However, when I tried to play a radio station on my Sonos system (this was several hours after the power outage) “unable to add to queue”. I then tried playing a track from my Music Library. Again, “unable to add to queue”.

I rebooted the router and verified that my wifi was functioning normally. The above problems persisted on Sonos. All lights on speakers were white (normal).

I unplugged the speakers, waited 15 seconds, plugged them back in. After the lights on the speakers turned white, I tried again. No success. Note that I tried both from the Sonos app on my phone and from the app on my laptop.

After a few minutes, I was finally able to get Sonos to play a track from my Music Library. After that, I was able to get the radio station to play.

So, the advice to reboot the Sonos speakers is relevant. It’s unfortunate that the error message from Sonos is nont more informative. Plus, it looks like it takes several minutes after rebooting the speakers, not the 1 minute in some of the help postings.