@EhDuh What color is the deco you are trying to add flashing? Are you trying to add it via Ethernet or WiFi? Try moving it closer to the main unit and see if that helps.

@intergram Beside trying the "Network Optimization" tool under the More tab you could try to reset both units by pressing the reset button on the bottom of each one for 2 seconds and then rebuild the...

@intergram Please try the following and get back to us. Go to MORE > QoS and ensure QoS is disabled. If you do not see an on/off switch for QoS, set it back to standard and remove all priority...

@intergram Have you tried replacing the cable? A bad cable can cause speed issues

@peacew You can also log into the web ui to find your hardware version if its not on the bottom/back of your deco units

@Karlito Please keep this in mind it is the weekend for the tp-link staff and I have seen them in the past reach out to the engineers to ask about new firmware and they always get the same response....