On my 2nd weekend flying the Mavic, I tried the Active Tracking - Profile to take a video of a car moving forward.  The Mavic was positioned 3:00 facing the car.  When the car move, the Mavic followed for about 14 secs then "disengaged" from Profile mode & trailed the car from behind.   The car was moving about 15 kph.

Is there a max speed in Active Tracking?  
Why did the Mavic stop Active Tracking?

https://www.facebook.com/juanch/videos/10210830303727304/