Just started having an issue that all vehicles are arriving but are invisible this doesn't happen all the time but 9 out of 10 times...
This has been discussed many times and, of course, it's not a GSX problem.
It seems there's a limit over the maximum number of objects the simulator can display and, with the recent release of extremely complex airports and AI traffic packages with injection, it's now much easier to reach this (undocumented) limit if you have your settings too high, resulting in the simulator not displaying objects at random.
From GSX, what you can do is to lower the maximum Passenger Density slider AND disable the "Extra Ground Clutter" option in the Config panel, however this one will only have effect on airports where the GSX jetways are replacing the ones of the scenery.
If you still have the problem, then you must reduce the number of objects in other ways, for example by reducing the number of AI injected planes if you use an AI traffic pack with AI injection.
