I never used wireless on my Roku 3. I just have it connected to my gigabit switch. My 5 GHz network is on channel 157 and my Roku 3 remote is on channel 165. I know wired is not a solution for anyone but I only run devices wireless if I have no choice. If it has a Ethernet port I run it wired even on the other side of the house and different floors.
Earthlink Standard powered by Time Warner Cable Brooklyn.
ASUS RT-N66W Router 374.43 (Merlin Build) using OpenDNS.
Amazon Fire TV, Apple TV 3, Roku 3, Sony PS3 Slim, Sony S5100 all Wired. Chromecast Wireless.
Toshiba 39L2300U 39-Inch 1080p. Nexus 5 on T-Mobile and Nexus 7 (2013).
Cats are the best pets.