Problem with persective

If I am in perspective mode, and I try to change a part fromhide to show, the view jumps to a slightly different location. Itdoes this if the view is static or changing. It doesn't do thiswhen not in perspective mode. Also, sometimes, if I turn a motor onfor a rotating and assymetric part, the view will shake, also onlyin perspective. I can address this by using a camera, but this isfairly clumsy.

I would like to know if this is a setting somewhere, a hardwareissue, or a bug in animator. If someone could try to duplicate thebehavior with something similar to the attached. Start with one ofthe components hidden and show it a couple of seconds in.SolidworksMotion Studies