Setting up Circle with the ARRIS NVG589? Unable to connect to the Internet while Circle is plugged in over Ethernet to your router? We'd recommend disabling a feature called IP passthrough.
A common setting in AT&T branded routers (usually manufactured by Arris) is "IP Passthrough", which will cause issues between the router and your Circle device if connected via ethernet. If you'd like to use the Circle device over ethernet, please make sure this setting is disabled. You can read instructions for doing so here.
Once you've got that disabled, go ahead and set up Circle again while plugged in over Ethernet to your router. We've found that this particular router does really well over Ethernet but not when connected Wirelessly.
Other possible workarounds
Enabling compatibility mode for Circle may resolve some of the above issues. You can read more about compatibility mode here.