Issue with Xbox One Wired Network

I have an odd issue with the official firmware (and Merlin) with my RT-AC66U router that I can not find out. When I have my Xbox One wired to the router (Cat6), every 30-60 minutes, the router will reset. As soon as I unplug the cable, the Xbox One connects via wifi, and the router is stable, and run for weeks. As soon as I plug it back in, the router begins resetting.

For curiosity, I installed Tomato and DD-WRT on the router to see if the same things happens. When either of those...

Issue with Xbox One Wired Network