Cruise Control problems of the 2014 Toyota Sienna

On Saturday, June 6, 2015, my 2014 Toyota Sienna limited automatically braked with very significant force while the cruise control was engaged at approximately 45 mph. No vehicles or obstacles were ahead and I was driving on a straight and relatively level street that has a 45 mph speed limit. This problem also occurred many, many times in the first several months after purchasing this vehicle new in April 2014. I reported this problem to molle Toyota, kansas city, missouri when it first happened and at the 5,000 and 10,000 services and they could find no problems with the adaptive cruise control system. During the first few months of ownership I tried driving to the molle Toyota dealership when the problem occurred and the dealership was open but each time the problem stopped happening before I got to the dealership. The problem usually happens "out of the blue" after I have been driving for a while. Once the problem first occurs, it then happens over and over each time I reengage the cruise control. Stopping the vehicle and restarting the engine almost always stops the problem from reoccuring. And as I indicated above, sometimes the problem will stop on its own without restarting the engine. I am submitting this complaint at this time after seeing in the news that there have been similar complaints on jeeps. The June 6 incident was also much worse than previous incidents due to another car following very closely behind me when the Sienna brakes automatically slammed on. I was also concerned that the driver behind me might have thought that I had braked hard on purpose. I have been able to cope with this problem but my main concern is with allowing others to drive the Sienna and that they may not be able to quickly turn the cruise control off when the problem happens.