It's a VA loan "refinance" scam.  I only know because I called it back from my work # just so my home phone wouldn't be added to lists of good numbers that are sold and resold.  They start off by giving a spiel about an approved government program that's guaranteed to save you thousands on your existing loan and that I've already been qualified and approved for these savings.  Keep in mind I CALLED HIM, so he had no way of knowing anything.  He asked if I had a VA loan - I said yes (which I really do have).  He asked if it was fixed - I said yes.  He then said, "Great!  Let's get started to reduce that interest rate!".  I said, "Great!  I didn't know anyone was offering fixed rates below my current rate of 2.25%!" (which is really my current 15-year fixed rate).  He then proceeded to say it's impossible for me to have such a low rate and hung up on me.

Lots of noise and other people talking the background - definitely a scam being run out of some boileroom call center.