Everyday this week, at about the same time, I get a call from these people and they are calling from different phone numbers with different area codes. This area code is from Michigan. Yesterday it was a 610 area code - Pennsylvania, day before it was a 505 area code - New Mexico. Crazee!
No one responds when you answer and then after several seconds, they hang up. Probably harvesting contact names so other telemarketers can ask for you by name.