Be careful if you answer! There is a scam going around where they can record your voice. They ask if you're there or if you can hear them. Once they have the "yes" it's remarkable what they can do with that. There's was just a news story on the scam. Don't answer!
They called several times over the last few days and shows up as "Out of Area". Answering machine is not on. Know idea who it is but "Out of Area" is as bad as "Unkonwn".