When I answer there was a silence so I decided to hang up but they have been calling from different numbers doing the same thing

My teenage son gets a call from this number on his mobile phone everyday. No one else in the family receives these calls. Interestingly, he's also the only one with Facebook & Twitter accounts.

I pick up and say hello and an automated voice of a lady says "hello" then hangs up. Twice today- kinda creepy. Why??

Same experience here, and it happens almost daily exactly at 4.30pm. Today, I called back, and it was a female automated message "For English, press 1", "For Arabic press 2". After pressing 1, it asks you to enter a known area code or something, or press "*" for an operator, at which point it straight away says "all operators are currently serving customers, please continue waiting". Then I decided to hang up, because this is obviously very dodgy, when a company doesn't specify name, and gives calls that hang up regularly. Perhaps it is a scam where they make money while you hold the line? If anyone is game enough to call and hold, please let us know what the result is...Thanks!

Number called again today - there was a silence... and then an asian voice "sorry i have wrong number" hang up.

Same experience here, and it happens almost daily exactly at 4.30pm. Today, I called back, and it was a female automated message "For English, press 1", "For Arabic press 2". I hung up after this ... but what is it!!!!