Not a scam, its a bill collector.  My phone number used to be owned by a real loser.  I get calls looking for this guy all the time (he showed up in the local police blotter a while ago so I think he's doing time now).  Unfortunately, they never seem to believe me when I tell them they guy is not at this number.

This number has called me a few times, never leaves a message. I have no idea who they are or what they are looking for... ugh! so frustrating.