So, at the weekend I noticed that our Lounge (Arc, Sub & 2x Play 3) was missing from the App. As was the Port in our garden cabin.
The rest of the house (Conservatory with a Sub & 2xOneSL, the Patio with 2xPlay1’s, a stand alone Play1 and the Kitchen with 2xOneSL & Mini-sub) were all working well. Note; one Play3 is hardwired, all other components work by WiFi. Port in Cabin is connected by Cat5 or 6 cable to a TP-Link router. Always worked fine.
Back-story: Previously with Virgin Media - rubbish connection, drop outs etc. Tried with & without Boost, hardwired one Play3 etc to no avail. Switched to Sky Max Hub in September 24. Sky extender pod added to system in February 25 to help WiFi around house & get rid of black spots , all working great. Second extender pod added early March. We are now mid-March.
I tried Factory Reset, re-adding the components, Rebooting each of the products and rebooting my Router, but none of it seems to work.
The closest I get is that some products say they have been added but that they may not show in my system and that I need to unplug the power cord and plug it back in to complete the process. I have done that, but they still don’t reappear.
I spent nearly 2-hours on the phone with Sonos support last night, trying similar things to what I had previously tried, including unplugging the extenders, but with no joy.
In fact my system is now worse, as (at their request) the Conservatory was rebooted & factory reset, even though it was working, only it never came back on line.
They are now suggesting that I ring my ISP and request that they turn off my WiFi 6 and make sure my 2.4GHz is working on BGN 802.11.
I am concerned that turning off WiFi 6 will reduce my security and speed of connection for work?
More to the point, Sonos own website help suggests you keep WiFi 6 and leave the router to manage itself.
I am rapidly losing faith in this system and do not trust the advice I’m getting, as it appears to compromise the whole premise of why I upgraded my WiFi and they seem to be trying to find a convenient ‘fix’ at the expense of compromising my non-Sonos equipment. It also doesn’t make sense to me that the system has been working fine up until the second extender was added.
If I have to, I will go back to just one extender, but at the moment that doesn’t appear to a potential solution as we cannot get the components re-established with none of them plugged in.
Does anyone have any serious/sensible advice or opinions on how I can get my system back up and running consistently?

