Sun Roof problems of the 2012 Volkswagen Jetta

I was traveling down the highway this afternoon going 70 mph. All of a sudden, my mother and I heard a loud boom, it sounded like a gunshot. Glass from the sunroof suddenly covered us, the front seating area and the back seat. We were the only car in the highway, there was no evidence of any external object being thrown at my vehicle and the sunroof glass s pushed up, indicating that the explosion happened from inside the vehicle. I've read of several instances of this happening and feel this is a real safety hazard. Lucky, I didn't lose control and we were just shaken up, but this issue needs to be addressed. All of my windows were up, the sunroof was closed, there's no reason for something like this to happen on a car that isn't even two years old.