@KC6IJM Wow, on a brand new unit? Well, I returned mine, but they were refurbs, so I wasn't surprised that mine were bad. But a brand new unit has me a bit suspicious. I mean there isn't much to this...

Well, last night I took the whole thing down, hit the factory reset buttons, and tried to re-create the network using one of the other decos as the main unit. Well I ended up trying all three, and...

@Tony Small update. I haven't tried swapping them yet to put one of the other two in as the main deco yet, (I'm working, and can't totally drop my internet at the moment) but I did remove one of...

Tony wrote @paqman Swap the main unit with one of the satellite ones to see if the issue still happens. If the ones wired to the switch continue to blink red, take one directly to the main Deco,...

So I just picked up the three pack of the TP-LINK Deco M9 plus for our house. According to the diagram at the top of this page, I have them hooked up in the "star network" configuration. Main deco is...