Might try a different outlet. If that doesn’t work, I’d be exchanging it. Tends to be faster than trying to get an RMA

Thanks for the reply. Definitely not an outlet issue as I tried 2 different ones which worked for other devices 

Since you tried connecting the modem with a different power outlet and power cord, I would suggest factory-resetting the modem.

http://arris.force.com/consumers/articles/General_FAQs/S33-Factory-Reset

After the factory reset, if there are no changes in the behavior, I would suggest visiting www.arris.com/consumersupport for a warranty claim.