Grandstream HT502 Stopped Responding

Dang it! I opened a service ticket, but thought I'd try here as well. My HT502 stopped responding today with very ominous looking symptoms. Both the amber and green lights on both my LAN and WAN ports are constantly lit. In fact, both stay on constantly regardless of whether a cable is plugged into them or not! I think something fried, but on a hunch I've unplugged it for a while in case it got too hot.

Suggestions?

==== Text of Service Ticket ====
Today my Grandstream HT502 stopped responding. It will not register regardless of whether I have it behind the router or in front of it. I have repeatedly disconnected the power, waited 30 seconds, and reconnected it to no avail.

The Power, WAN, and LAN lights are constantly lit, but Phone 1 and Phone 2 are not.

IMPORTANT: The amber and green lights on both the WAN and LAN connection are ALWAYS ON. They stay constantly lit regardless of whether there is a cable in the port or not.

Follow-up:
Yesterday I submitted a ticket and braced myself for the inevitable talking in circles with a customer service rep who didn't really read the ticket and would want me to try everything I already tried before escalating it. It didn't happen. Instead, Gerard J cautioned me not to hit the reset button while they researched, and later Erik H mentioned that they are shipping a new ATA configured with both numbers I subscribe to. Done! That easy.

I'm guessing something fried in the HT502. I'd really like to know what and if there's anything I can do to prevent it from happening again. But overall, I'm actually impressed by how quickly this got taken care of. I suppose I shouldn't be impressed with customer service reps actually performing customer service. But I've been run around by so many other companies that I find it refreshing to describe the problem and have someone actually read the ticket and respond to what was written.

Thanks VOIPo.