Representing themselves as agents for IRS. Tape recorded message. When I caled back I informed the "agent" who answered the call that the IRS NEVER calls people. They notify delinquent taxpayers by regular AND certified mail as a follow up. I also informed them that impersonating a federal agent is against the law, BIG TIME. Tried to tell them I was going to report them but they hung up, really fast.
Some mother sodomizing syphilis infected fool called and told me that the US Treasury is investigating me and that if I ignore his call I'll be guilty of a criminal offence. So I told him I do not talk to or listen to him and to go back to copulating with his pet pig.
You do not have to keep placing your number on the DNC. Once its on, its there until you remove it or change it. All you do by re-registering is open yourself up to legitimate business calling on top of all the scammers and illegal calls for 30 day's.
By State DNC lists:
http://800notes.com/res/DoNotCall.aspx
The DNC isn't a call blocker and can not protect you from the illegal callers, extortion scammers, foreign country's and frauds. Criminals do not obey laws simply said. They use spoofed numbers which make it hard to track them down.. it takes time to do this and many subpoenas for call records.