Yes, 2013.
It would pop over bumps, during turns, braking, accelerating. It took some time, but I narrowed it down to the seat. I could duplicate the pop by bouncing around in the seat or forcefully grabbing the seat and moving it side to side.
I took it to the dealer. They said it was a seat track. They ordered a new track and started tearing it apart. It took almost a day, as the dealer said it was a much bigger job than they thought. They called me mid job and said that some type of brace that hooked to the center console had also come loose.
I got the car back after the fix. Guess what-still pops. Much quieter than it was before, but it is still there. Of course I'm listening for it and am very anal about my car.
I'm going to let it continue for a bit to see if it gets louder like it was before. Then it is going back. It drives me nuts to hear it.
Let me know if you have any better luck fixing it so I can report it to the dealer.