Strange behavior in Safari when drop down lay over Youtube embed code

This bug only appears in Safari. When the drop down menu touches the YouTube video in the side column, the text scrambles. Hovering over the text in the menu returns it to normal.

I’ve pinned it down to the slideDown() behavior. If I change it to show(‘fast’), the problem goes away.
It also doesn’t appear without Javascript relying on the css hover states.

page:
http://www.cynergydata.webventions.com/partner-solutions/iso-partners-solutions/donatewisenow/


       $('.nav2').removeClass('nojs');

	$('nav li').hoverIntent(
		function(){
			$(this).find('.nav2').slideDown('fast');
			$(this).addClass('active');
		},
		function(){
			$(this).find('.nav2').slideUp('fast');
			$(this).removeClass('active');
		}
	);

Does anyone have any ideas how to fix it?

Thank you,

E

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