Hi folks,

I'm just setting up my home network for the first time, in a new house.  10 rooms are wired with CAT6A cable to the basement where the equipment is located.
I've already got Xfinity successfully installed and operating, and I'm using my own modem: Motorola MB8611.  This works. 

Initially the connection looked like this:
Xfinity --> Modem --> Switch --> 10 wired locations.

When I connected my laptop using 2 different wired connections to the TPLINK switch, I had great connectivity.

I then downloaded the DECO app to my phone.

I then added the first DECO mesh router wired directly to the TPLINK switch, and attempted to install the router via my phone, and this didn't work.   
Xfinity --> Modem --> Switch --> DECO. 
No internet.

Then, I deleted that mesh router from my app, and wired things this way:
Xfinity --> Modem --> DECO --> Switch --> 10 wired rooms. 
When I then added the mesh router to my system using my phone Deco app, this gave us wireless internet to all our wireless devices.  Hooray!

But now the wired devices aren't getting internet connectivity.  We may have had wired connections for a little while, and then they couldn't find the internet.  Very odd.  

What am I missing, and/or doing wrong?

MANY thanks in advance!