Just like Mrs. K I had 3 calls, 2 voice messages and 1 that my wife answered today from the robotic voice that stated this is "final notice" that the IRS is filing lawsuit against me and I should call this number for more information. I agree that this is a SCAM the US Gov. does not do things this way. They would send a certified letter or a hand delivered subpoena.
Their automated system said they were the IRS and were creating a lawsuit against me and to call the number for more details. WHO DOES THAT? Just serve me! HELLO! Scammers aren't that smart... Go get 'em IRS!
Same call..they are filing suit against me. When I called... Not an automated phone answering service, but a live woman with a thick English accent answering ;saying this was IRS audit. When I asked who to prove who she was, as IRS sends a letter vs calling, woman disconnected on me.