Quicktabs not working on some IE8 machines (most of them are in China)

I'm running quicktabs on a number of pages, everything works wonderfully in all of my testing and all browsers but we're getting an uncomfortably high number of complaints from people using IE 8, most of whom are our customers in China. I can't replicate the issue for the life of me so this is really tough to nail down, maybe its a loadtime issue? The tabs are being rendered through Panels, pulling a Views block with the QT arguments added in the Quicktab config (not handed through the URL).

Can anyone else replicate the problem? People claim they cannot access the 'Documents' tab at the bottom of the following link -

http://www.microstrain.com/inertial/3dm-gx3-45

I appreciate anyone's help or advice on this...