Help please
I can't figure it out for the life of me.

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You mean.... this:
Simply paste the embed between the tags [ youtube ] [ /youtube ]
(No spaces)
Do as was said above, then highlight the whole thing you have posted... then click "remove link". It should be found along the icons at the top of an advanced post edit.
It isn't working, I'm guessing, because there is hyperlinked text within the code which is confusing it.
I had that exact same problem until I figured that out.
[ youtube]<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/9UMedd03JCA&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/9UMedd03JCA&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>[/MEDIA]
[ youtube]<object width="425" height="344"><param name="movie" value="<A href="http://www.youtube.com/v/9UMedd03JCA&hl=en&fs=1"></param><param">http://www.youtube.com/v/9UMedd03JCA&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/9UMedd03JCA&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>[/MEDIA]