Not sue what “common thread” you are referring to, other than some routers do a crappier job of WiFi than others which causes random device dropouts. Ones are rock solid devices, the only devices with iffy wifi are Symfonisk v1 and a few Playbars have defective wifi cards.
What router are you using currently?
“common thread” just a simple Google search or a poke around this great community...also the fact I am here in 2022 asking about something dropping off a wifi network…be that as it may I do love the devices...
Router: ASUS AX XT8 running tri-band smart connect
My ZP is wired in...if I wire in the One it is fine...when it is connected to the wireless it works fine no drop-outs anything like that...it just at some point drops off the wifi...I am assuming drops wifi as Google assistant can’t find it, the One disappears off the app and my iPhone won;t can’t via AirPlay to the One…
Cheeers...
Asus, if you search these forums, has long been known to have irregularities when being used with Sonos. This might be at least part of the issue, although it also may not be, as you claim to have a ‘ZP’ of some type wired.
If your system is indeed using SonosNet, that points to a more likely issue of a duplicate IP address. I’d certainly suggest a simple network refresh bumpy unplugging all Sonos devices from power, then rebooting your router. Once the router has come back up, plug back in the Sonos devices, wait two or three minutes, then see if the ‘disappearing’ act has gone away.
Cool cool...will that a try and see what happens thanks…
Also I "lied" I have a Connect hard wired...I just checked in the Sonos App…
Does make a difference if wifi is enabled or disabled on the Connect when wired in?
Thanks again...
Does make a difference if wifi is enabled or disabled on the Connect when wired in?
Keep the WiFi enabled on the Connect.
The radio in the Connect is used to communicate with your other Sonos devices over SonosNet, so needs the wifi setting enabled.
@steve-waters can you confirm the Connect is wired to the Primary Asus node, not an XT8 satellite.
Furthermore, in the Asus router app, do you see all your Sonos devices listed under the Primary Asus node?
Yes both are connected to the primary node/router in App...the Connect via wired...One via wireless…
I have done some more searching and just disabled the QoS on the router...although shouldn't make a difference as they are now on the SonosNet...as I have removed the WiFi setup/access to my wifi network…
Let's see how we roll now...if it still disappears off when using Sonos network...will reenable the wireless and try again…
Cheers
Airtime Fairness was another setting to turn off with the Asus router when using WiFi. Another possible fix was factory resetting the nodes after Asus firmware updates.
I’ve got the XT8 and not had any problems with speakers disappearing, whilst using SonosNet, so hopefully your issues are behind you.
Fairness was off on all three wifi...with any luck setting up on SonosNet should get this happening…
Thanks folks for the responses… 
