@David-TP it wasn't beta firmware it was just the standard firmware it auto updated to. Thatdoes definitely sound like a similar issue however in my case if I set a connection preference that wasn't...

No I didn't

Nobody ever responded to the report

Sure thing I will fill in the report now. This affected 6 different decos in exactly the same way and the only way I could regain functionality was to install firmware 1.6.4 manually back onto each...

Deco m9plus v2 if they are updated to any firmware beyond 1.6.4 and you try and select a connection preference then they devices will brick and needed to be reset. During initial setup they will only...