I keep getting calls from this number, but no one leaves a message.  I tried to call it back and it's a fax machine.  I looked the number up in google and it belongs to the Scottsdale (AZ) Convention Center & Visitors Bureau.  Odd, very odd.

Keeps calling never leaves a message

Rec'd call from this number while I was on phone.  When I tried to answer, the caller had hung up.  ????