@JimJano Did anyone get a real solution to this problem please? I have just started facing this problem on one of my satellite Deco P9's for no reason at all. I tried restarting, rebooting, moved it closer to another satellite that works fine and yet this satellite just drops connection randomly and flashes red and back to steady white and flashing red again going back and forth like this all day.

@JimJano 

I am facing the same problems. After nearly year oif working fine, in an isolated house with no interfering networks units started randomly dropping out and blinking red, even in rooms with a decent WiFi signal from the base unit and, in one case, with an Ethernet link!

After trying everything to no avail, in desperation, I deleted the whole network and started from scratch. It seems to be OK except that one of the (four) units refuses to connect, even at 50cm from the base station, connected by Ethernet to the fast ISP fibre optic modem.

So, what can I do? I have tried the reset button, still always ends up blinking red.