Got the same call. Never give out personal information. They had really thick accents. Asked for someone who wasnt me then asked who i was. Started threating me anout 2013 taxes. Told me some badge #then told me i could be in a lot of trouble. Then called back a couple days later and tried the same thing.
"Hi my name is James Caston and this message is intended to contact you regarding an enforcement action executed by the United States treasury intending your serious attention. Ignoring this will be an intentional second attempt to avoid initial appearance before magistrate judge or a grand jury for a federal criminal offense. My number is 224-592-0127. If you can. It's 224-592-0127. I'd like you to call with us and help us to help you. Thank you." There was no company name mentioned, it sounded as if it was a computer generated or enhanced voice (robotic). The message was left on our voice mail.