go to this page where you see the problem
and then CTRL+F5 .. this will force the ‘player’ to reload and should then get you where you need to be.
if it doesn’t then close ALL browser windows and try it again.
re these ‘other’ machines, are they also using IE7, and have they been used previously to access the application ? if they have, then the same ‘caching’ issue may be occurring for them as well