Hello Jman

                    When the intermittent connection issue happening only on Wi-Fi we would suggest you to try changing Wi-Fi channels will avoid interference and that will give better speed and connection. Basically, If other Wi-Fi sources such as neighboring wireless access points are using the same wireless channel, this may cause intermittent connectivity issues, even if the competing signal is relatively weak. Changing the wireless channel within the  gateway can improve connectivity. So please follow the steps mentioned on link below

Let us know if this helps