Google Chrome, Flash and z-index wrong behvaiour
You can add a wmode parameter by query string.
Ex: src="http://www.youtube.com/embed/LSaoRSlqQzw?wmode=opaque"
The problem is probably with the wmode of your flash player. Try "wmode=opaque", which means it should play nice with your z-orderinghttp://www.8bitrocket.com/2011/02/11/quick-guide-to-wmode-and-flash-embedding/