We cannot replicate this problem, and of course it's just you two ever reported it but. it's possible that you have so many addons and too high settings, and the simulator is so spammed by having to process too many commands in a short time, because too many addons try to talk with it, that it might have skipped some of the commands we sent from GSX, for example the command to remove the static jetways to replace it with a dynamic one.
How many addons you use ? Do you have a 3rd party weather engine ? Does it make any different if you turn if off ?
Try first a default airport with a default airplane, maybe if the sim is less stressed out in such situation, it might confirm my theory.
Also, be sure you don't have the "Pause on task switch" option enabled.