I am animating a gearbox that consists of two subassemblies (input and output shafts).  During the animation I am showing and hiding parts.  The problem that i am facing is that when i hide one of the subassemblies then show it further in the timeline all the appearances that the subassembly has becomes the default color.  I am only creating keyframes for the appearance.   Anyone know what could be causing this?

Abhinav