Ok ... I think I may have traced the source of this mess. I'm working with CAD files from one of the automotive companies for future product lines. These files are converted to .mb format for studios like mine to use with Maya. I've noticed one file in particular always displays this corrupt behavior. Once this happens ALL subsequent files display the same behavior. As long as I don't open this file everything seems to work fine. I think the random nature of the problem stems from other files with this same corruption. I'll have to pay close attention for a common thread.