TBH, I don't think it's MC itself as I've just quickly tested it myself in both fullscreen and windowed mode. In windowed mode, opening and closing browsers, explorer windows etc had zero impact on the signal.
Again, the only pause I had was when transitioning from full screen to windowed mode and back again.
As to the culprit - I would be more inclined to initially place the blame on a driver
problem/incompatibility. Particularly if the Kworld drivers
aren't 'Seven native' drivers.