I apologize if is described somewere else but i have been googling and I could not find a solution. the issue : floating and under basment jetway weels, erroneous placment of jetway onto the plane, only the front airplane weel in rare occasion vibrate as if it was not placed 'on ground' (this last tested only with QW 752)
Yes, it has been discussed many times already, and it doesn't really have anything to do with the scenery, it's a bug of the FSX jetway system, specifically the wheel lock on ground method, it's a confirmed FSX bug:
http://www.fsdeveloper.com/forum/showthread.php?p=71060#post71060Torgo3000 (Adrian Woods) is one of the original FSX developers. We can't do much to fix it, other then possibly replacing the system with something entirely custom, and then patching all our existing sceneries to use it. It's something that we are planning to do in the future, but for the time being we have to live with it.