Hi @an63.

Thank you for reaching out to Sonos Community.

Since multiple speakers are missing can you submit a diagnostic report for me to verify what's going on in your speakers?

While waiting for my reply try the following troubleshooting steps to prevent Sonos speakers from disappearing from your Sonos app. 

Adjust the speaker's distance to the router

If your speaker is far from the router, it may be struggling to stay connected to your wireless network. Try moving the speaker closer to the router to prevent future drops. If your Sonos system is in a wired setup, move the speaker closer to the next closest Sonos product.

Clear up any wireless interference

Wireless interference can contribute to issues like Sonos speakers disappearing from the app.

You can visit our article on reducing wireless interference to learn how to change wireless channels and move Sonos away from certain electronic devices in order to avoid interference.

For more information you can visit this article: Speakers missing from the Sonos app

Let us know if it works. If you need help with any other information, please be sure to let us know.

Hi Mark / Sonos

This is really strange, it’s not allowing me to add product or find missing product by either route.

Wireless system but the 2 main paired ones are right next to the the hub.

Surprisingly one of the sonos ones (1 out of 3) appeared on the system last night but has vanished again today.

I’ll submit the report and hope this is an easy fix.

thanks andy

@an63 i have the same issue - after S2 my system is a complete  wreck.

Hi

For other reasons I restarted my router and everything came back to life - all sonos products available and also set up on ipad/ iphone and laptop.

Try it - I hope it also works for you!

andy

Same here. What was a week-oiled system is now intermittent. Speakers come and go Willy milky. No change in WiFi. Same router. Same speaker placement. Same NAS music library. The only change is the app. 
 

im probably salty after the optical port on my Playbar crapped out, but the ‘advancements’ being made are the opposite of forward for me. 

Again, try a network refresh. Unplug all Sonos devices from power, then reboot the router. Once the router comes back up, plug back in the Sonos devices.