I hear the same thing! I thought it may have something to do with the door panel creaking a bit, but it sounds too "perfect" in that it clicks twice each time.
It's like I'm trying to roll up the rear drivers side window when it's already closed. It clicks on to roll up and clicks again to stop almost immediately. I'll try to grab a video next time I'm going somewhere.Where are you hearing this on the car? I occasionally hear a click here or there, but can't reproduce on demand. Can you reproduce on demand? If so, then try recording with your phone. There were reports around here about a loose bushing, nut, or something on the axle of some Volts.