Hello, I did not see a problem similar to my experience with the C5400.  On a regular basis the router does not seem to let some devices communicate to the Internet.  For instance, when I try to start Netflix on my TV or Blue-Ray player, I get an error message that something is wrong with my network connection.  Both are plugged into the LAN with Ethernet cables.  I reboot the router and then Netflix works on both devices.  I tried to install a Ring doorbell last night.  It would connect to the 2.4 Network, but could not access the server on the Internet.  I rebooted the router and the installation finished correctly.  I tried installing a Tan Tan switch tonight.  Same thing.  Once I rebooted the router the installation worked correctly.  Our PCs work fine.  My wife's is on Ethernet and Mine is on the 5G network.  Other devices I have, such as Smartthings, Arlo cameras and Ecobee do not experience a problem.   Any thoughts on what can be causing this?  There are 42 devices connected to the router, 11 wired and 31 wireless.  We ocassionally stream a movie, but other than that our traffic is fairly light.