Working on a web site that dynamically (i.e. upon user action) shows and hides HTML content and Flash content, everything worked as expected in IE9.
When I checked the same page in Chrome 18 and Firefox 12, however, the Flash object would reset everytime I invoked the jQuery .show() method on the object (initialization takes some time for some of the objects I embed).
My solution was to roll-back some of the changes I made, and put the Flash object back to its iframe. Toggling the iframe display does not seem to affect Flash.