NETGEAR AC1750 / C6300 wifi cable modem router LAN connectivity problems

Any suggestions or advice on helping me sort this out would be greatly appreciated. I installed my new modem/router a few months ago and noticed that when I try to stream movies over my Xbox 1 or Raspberry Pi3 they stop every 30 seconds or so, freeze for around 10 to 15 seconds, and then play for another 30 seconds or so. At first I thought it was a buffering issue, but im not convinced. When playing an online game, approx every 30 seconds to a minute I get a poor connection error that stays onscreen for 10 to 30 seconds and will sometimes drop me out of the session. Both devices are connected via CAT5e cable.  I never really noticed a problem with my cell phone or laptop having problems when I connected wirelessly and surfing the internet, but then I'm only looking at static pages and if my wifi signal dropped on my cell phone I figured I was just out of range in my backyard.

As far as troubleshooting, I have only the Xbox plugged into the router right now. All WIFI devices are turned off. If I powercycle the router, I can get Plex and HBOgo to stream for about an hour or two. If I let the unit sit overnight, I need to powercycle the router again. Even if I leave the Xbox on all day, when I get home from work, I need to powercycle the router in order to watch shows.