Hi @stephen s, welcome to the Sonos Community!

More likely, this is a network or interference issue if one of the Play:3s drops while the other doesn’t. I would suggest you check out our article on wireless interference and follow the advice listed there.

I would also recommend you reboot your network and Sonos system by powering them off for one to two minutes, as this can also help re-establish connection between your router and players. If rebooting does resolve the issue, then this thread may explain why:

If following the article and rebooting doesn’t help, then I’d recommend submitting a diagnostics when this next happens and replying here with the reference number.

I hope this helps!

Hi Jamie A thanks for your reply. I checked out the wireless interference article. My router is dual band (2.4 and5 ghz).   The 2.4 band was using Chanel 11 already so I changed to 6. When I went to the Sonos app the speakers could not be found and the pop up setup screens could not find them or reconnect. I left it for a while and when I went to try again both speakers were there! One was on the 2.4 ghz band and the other on 5ghz band. I set them up as a stereo pair again and the system has been stable now for 2 days. The app is also now responding quickly to commands- e.g. volume up. Thank you for your help. 

Jamie A - sorry to have to come back to you again but I wrote too soon . The problem is still there.  The app says it can’t find the system- sometimes even if the speakers haven’t dropped out. Sometimes it corrects itself other times I need to go through the popup screens. I moved the speakers in the room a bit closer to the router but still happens. All other devices in the room- tv, tablets and phones all work perfectly. As I write the left speaker has just dropped out and come back in again a few seconds later by itself. ‍♂️

It sure seems like a potential duplicate IP address issue to me. Granted, one should never rule out wifi interference per se, as just changing the channel doesn’t always get it out of the interference possibilities. 

Try this: unplug your Sonos devices, all of them, from power. Then reboot your router. Give the router a couple of minutes to come back up, then plug back in all Sonos devices. Give them a couple of minutes before trying a test. Granted, it may take a while. If this fixes it long term, look into how to set up reserved IP addresses in your router’s manual, and it will be a more permanent fix. Any router that has gotten into this state once could easily do so again, and reserving IP addresses protects against that. 

Thanks for this. Ok I’ll try that tomorrow. Are you suggesting the problem is with the router? It is a new bt smart hub and I have full fibre connection into the house. 

It’s certainly a possibility. Anytime you change a router, it makes sense to reconnect everything, to ensure the DHCP table is clear. And reserved IP addresses is just good housekeeping for a network, Sonos or no. I have them set up for any ‘permanent’ device, and leave a section open for floating devices, and friends who stop by. 

Speed of your internet (fiber to your router) isn’t something we usually worry about, it isn’t an issue. We are usually most worried about the quality/speed of the connection, wired or unwired, between your speakers and your router. Your local network. 

Hi, I tried the solution above. It was stable for while but now dropping in and out again. Not coming with up the ‘unable to connect’ so much. It takes about 30 seconds for the system to respond to the volume being turned down. If I change eq settings they change back after about 30 seconds ‍♂️. I have submitted a diagnostic. The ref number is 1250644741

For a faster response and a tech with the best tools it is good to call support with the diag  number.