Probably. In time it gets worse. If your area is hot, the mini gets very hot and the processor slows down to cool itself and then the video lag gets worse. Just the nature of the beast.
In talking to the Autologic/Hangar Autopilot people they recommended the Pro model if you want lag-free video. Even the Air 2 is off their list now (I know as mine is starting to show the "Lagging video of impending death.").