Forgot to mention, I also have three Deco M3W units (Firmware 1.0.5) in the network, via WIFI - it's a big house. All the units are up to date with the latest firmware. I have also tried removing the...

I have Deco P9s connected in a star arrangement. MY ISP in the UK is Virgin. The main deco connects to a small 5 port switch (originally a TP-Link switch, later a new Netgear one - no difference at...