How big is your home? 

Is the router centrally located? 

What’s your budget? (don’t want to recommend a high end system when you only need something smaller). 

What speeds do you pay for? 

What speeds are you getting on the peripheral? Reason I ask that is that standard single/dual band extenders drop the speed through them by 50% by the nature of how they work. so if you’re speeds as the peripheral aren’t to low, a extender won’t help. 

Thank you for the response. The main problem was a TV. I switched it to the 2.4 ghz channel and that seems to have solved the problem.

To answer your questions though:

House is about 2800 sq ft. The router is against an outside wall, but in the middle otherwise. We pay for 800 Mbps and am getting 400 Mbps in the room in question (on the 5 ghz channel). 

If you have any thoughts, please let me know. Thank you!

I’m surprised that switching to 2.4ghz fixed the problem. That network is slow and sensitive to interference. 

If you’re getting 400mbps in that room, an extender isn’t going to boost the speeds any. It might hav a better wireless chip in it and you could direct hardwire in the tv. You might see a benefit there. Or using one of Arris W6U setups.