Spotify can't be seen from apps and PCs on satellite Wi-Fi extenders

[mikeaspatrick]

Hi, I have a new Orbi 850 (wouldn't let me select that exact one in the associated products box) router with two satellites.  The Orbi router is in my gîte (outhouse) where my office is, connected to a Starlink dish in bypass mode.  It's set up with two networks, a main one on 10.0.0... and a guest network on 192.168.2...

That router is connected to my house by an underground heavy-duty ethernet cable.  In the house are the two Orbi satellites, both connected by Ethernet as my walls here (I'm in France) are about two feet or more thick.

Absolutely everything works perfectly, except Spotify.  I have quite a few smart speakers dotted around my property from Amazon and Bose, all running Alexa.  A couple of them are on wired ethernet and all the others are on Wi-Fi connected to the guest network.

The problem is that all the smart devices in my gite that are either connected by ethernet to the main router, or by Wi-Fi to the main router, can be seen by Spotify and work perfectly.

However, NONE of the other speakers, all the ones in my house, whether connected by ethernet or Wi-Fi can be seen by the Spotify app on my phones, or by the Spotify app on my PC and laptop.

I know Spotify likes devices when on Wi-Fi to be connected to the same network, which my phones and laptop are.  I cannot figure out what's causing this however.  I've tried all manner of troubleshooting operations but can't get past this basic problem.

The thing is, on my old Wi-Fi 5 Orbi system everything worked perfectly all the time.  The only differences there were that not every satellite was connected by ethernet, and the guest network was also on 10.0.0...

Does anybody have any suggestions please?  Many thanks.