For a mere $ 1 M ! What a deal ! <| sep |> it can be a few things . when you connect to the wall outlet w the cat 5 e make sure to disconnect your wifi from your computer . check your network settings and confirm its connected directly no wifi . next step in troubleshooting . what is the N 300 connected to physically ? i assume it is going to a switch that then has endpoints in different rooms Cat 5 e labels on outletswhat type of switch is it ? that can be a limiting factor . also if you are only getting 42 mbps on wifi that means the routermodem combo is lack luster if you are paying for 162 . 5 mbps internet . I would buy a standalone router that has AC 5 GHZ dual band . Roughly over $ 120 for a decent one , blackfriday is imminent . Get a netgear Nighthawk variant .