I work for a state agency and we get calls from this number pretty much every day. When we answer, no one says anything and the call eventually drops off.
I like ur approach. Play them in return for screwing with us. These people are scum of earth ! Keep calling. I would use call Manager to forward the # to Trade commission ( 888-382-1222) but Vonage does not offer this feature ( offered by Comcast and Verizon).