I have a Ruida controller and this issue has been with me since I owned the 50W blue Chinese laser.
When cutting circles the laser will momentarily pause at each of the four circle apex. So when cutting a circle in the counter or clockwise direction it will start right then top with a pause then move left then pause then bottom and pause and so forth. These pauses are very momentary and exaggerated the larger the circle.
I’m figuring there is a setting for this somewhere.