Hi @OzLevent 

Welcome to the Sonos Community!

I am not in the US so I am not familiar with the equipment you have, but it is my understanding that the issue identified by the agent you spoke to can be circumvented by wiring a single Sonos device into the main Orbi node either directly, or via a network switch.

I hope this helps.

Yep same issue . To day constantly being told Sonos unable to connect to network . Sonos Amp , in the Uk iOS 16 . iPad and IPhone .  Switch amp off . Router off , even removed Sonos app and reinstalled .short success then  told   can ‘t find Sonos .Now 6 times in past 3 hours ( that is 2 devices disconnected 3 times ) had this problem some months ago but sorted itself out . Could it be another Sonos software issue ??? So frustrating . Ah music just stopped now , then just restated .  Doubly frustrating !!!!!

Connection problems which appear suddenly are often caused by network problems, not Sonos problems.  The  typical cause is duplicate IP addresses.  These often show up after an update or power outage because a reboot requires the device to request a new IP, and the router, having lost track of current IP assignments, issues a new IP that is in use by another device.  To cure this, do the following:

Reboot/power cycle your devices in the following order:

Modem
Router
Switches or hubs
Wired Sonos units
Wireless Sonos units
Computers/printers
Wireless devices - phones/tablets etc.

Allow each device to come back up before proceeding to the next.’

And then, to minimise the risk of the issue returning, you could assign reserved ip addresses for your devices. 
I had these issues, years ago. Since taking these recommendations on board, my system has been highly reliable, both between and throughout updates. 

Thanks folks. Will try above and see how it goes. (Not really sure what an IP address is , nor  how to assigned an IP address.)

In your router setup there should be a section that allows you to assign an IP address to a MAC ID so that device and only that device will be issued that IP.  You can find the Sonos devices’ MAC by looking at the serial number under About My Sonos System in the System Settings in the app.  The MAC is the serial number minus the last 2 digits. 

Usually (in every case I’ve looked at, which isn’t a ton), the process for doing so is in the router’s manual. And it seems as though each router manufacturer does it slightly differently, or enough to make it hard to put together a primer about it. It’s not hard to do, once you’ve done two or three….it’s just figuring out that first one that can seem intimidating. But it’s not...you’ll do fine :)

Hey, thank y’all for the comments. I tried everything as much as possible and as much as I could with my limited knowledge on the router issues. I turned off and on in the sequence as described above the router and Sonos equipment multiple times. I removed the extender from WIFI system since Sonos support said it is not supported. I connected the Play 1 directly through an ethernet cable which helped to find that equipment because Sonos app was not able to find it when it was connected via WIFI but only when it was wired. I also tried to assign a fixed MAC address to Sonos, which I am not sure if I could because the ARRES interface is allowing me to edit but is not confirming that it was assigned. However, either it finds or not, and in any of these trials Sonos app keeps giving the error “unable to play music” in any streaming app, like Spotify or TuneIn. The only thing I did not try is uninstalling and reinstalling the Sonos app. Any other idea?

I had a similar issue last night with a single One SL showing up as “Not Connected” and nothing I did to to that one speaker (reboot, factory reset, etc.) would make it connect.   

I have an ARC (wired through ethernet) and everything else (Sub, 2 x One, 2 x One SL) wireless.  I unplugged all of my Sonos equipment and deleted the Sonos app so everything Sonos was offline.  Re-installed Sonos app, restarted all of my Sonos equipment and added each device to a Room as they came up and eventually everything came back.   It took a few tries for some devices (namely the 2 surrounds).   Not sure if you’ve walked down that route already.   

everything except re-installing Sonos app. I’ll try.