It's probably searching for a boot server, and failing to find one. Is the coax cable plugged into it? Is it in the right port? Are there any intervening splitters? Maybe just try unplugging it for 5 minutes, and plugging it back in again. If it's still looping like that, that's the most likely scenario. If after unplugging it, removing any intervening splitters, making sure the coax is attached securely and plugged into the right port, etc. it's still failing, try calling the cable company and see if they're having any ongoing issues.