Philips Hue hub break DHCP address assignment over LAN on NightHawk Router

There is no ethernet switch in the config. The HUE hub directly connects to the router via eithernet. I configured a smaller DHCP range and set the HUE to a static address outside that. I saw no issues for a few days but last night the same issue again where wired devices were dropped from the network at the same time, and then could not receive a new IP via DHCP until rebooting the router. Will try updating the firmware with the hotfix mentioned in the other comment and see how that goes. 

Thanks for all help so far.