Just bought an r7000 and am having the same problems everyone else is.
My solution. Turn on access control and turn off password authentication.
You log into your router locally and define all your devices.
Everyone else won’t be able to login because they are not on your a list access control list.
Work around works perfectly.
The basic problem is the r7000 firmware section for authentication and encryption can not keep up with the packets associated with todays super high speed networks.
You can periodically use your smart device software to see who is trying to get into your network and decide if you want to allow….the default is not allowed.
This works for me and may or may not work for you.
Maybe someday an updated firmware will come out to address.
Model: R7000P|Nighthawk AC2300 Smart WiFi Dual Band Gigabit Router
