The car recently underwent a software update at the dealership for a backup camera issue. When I was driving home on the highway, the car suddenly braked and the seat belts automatically tightened up. This happened 3 additional times on the highway about 5 days later. I had turned off the automatic braking system and it seemed to go away. Then, with the system off, we experienced this again yesterday while on the highway at 70mph. The braking lasts for 1-3 seconds. There is no audible alert or dashboard display. IT renders the car quite unstable as it feels as though the rear brakes are being activated before the front. I reported this to the dealership and they want to inspect the car.