ESP8266 not connecting to my 2.4GHz wireless network.

Just recently grabbed a couple of EcoPlugs wifi outlets and decided to replace their crappy "phone home" firmware with something LUA based. For the life of me I could not get the ESP8622 to connect to my 2.4GHz network on my ASUS RT-AC68R/U. Even disabling encryption all-together didn't work. Eventually,I found that the answer was to go to the Basic Settings -> Network page of the router's admin interface. On that page in the "Wireless (2.4 GHz / eth1)" section I changed "Wireless Network Mode" from "G Only" to "B/G Mixed" and the ESP8622 immediately connected to my network. I have no idea why I needed to enable B mode but that was definitely the cause because as soon as I switch it to "G Only" the ESP8622 loses it's connection again.