Acrobat Excessive Screen Redraw

I have Acrobat 9 Pro (yes, I know it's old) installed on a MacPro (Mac OS 10.6.8) with lots of memory.

It seems that when working with a PDF with a lot of content (lots of images for example), clicking an object, opening a feature window (Preflight for example), clicking a menu to select a feature, or clicking a toolbar button causes frequent redraw of the active page.

Anyone have any ideas on how to stop or reduce this (some redraw I can understand)?

Thanks,
pd