I just upgraded from a Netgear AC1200 to a Deco M4 2400 2 unit setup.

My ISP provides "200" mbps but in reality its about 225. I was getting that with my old router.

With the Deco, my setup is: Cable>Modem>Cat6 Cable>Deco>Wireless to 2nd Deco.

I am getting about 85 Mbps with this setup, even with the 2nd unit off (I know that a wireless connection to the 2nd unit cuts the speed in half).

I have tried:

Swapping the main/slave unit

Full factory reset

different ethernet cables

Changing the QoS speeds to 225 and to 1000

Nothing seems to work. I've gone through a bunch of old threads with similar issues and nothing helped.