@Tomasm7 

same issue here. Reported it several times to the Support over the past years but no response. Other vendors are constantly improving firmware and adding new features but not TP-Link. 

  @Tomasm7 

From what you describe, Satellite Deco believes twice a day that Sonos Speaker is not a LAN client (like a desktop PC) connected to Deco by Ethernet cable, but device that provides access to your home network (like networking switch).

When Deco realizes it is connected to the LAN, in your case mistakenly, it switches to Ethernet backhaul.

Have you checked on Sonos forums and have you escalated that to Sonos support? It is quite unusual for a LAN client to suddenly advertise itself as an access point to the LAN. You couldn't be the one with Deco mesh who uses Sonos hardware, must be a topic for that on Sonos forums.

I also suspect this is not limited by just Deco, but any other WiFi mesh that can use Ethernet for backhaul.

Don't expect solution from the future Deco firmware. By design, Satellite Deco will switch to Ethernet backhaul if one is available. Satellite Deco will do that automatically. That will not change with future firmware. I have tested that with firmware 1.6 for Deco M5 which allows to set preferred Signal Source for Satellite Deco connection. Ethernet link overrules that setting.

  @David-TP 

Hi David,

All is connected exactly the same way as per your picture.

When satellite connects to sonosnet it looks like this with no devices connected. All devices reconnect to other satellites.