Did a quick test with qtranslate on my test-blog (http://futtta.be/wordpress/ru/blog/2015/05/07/youtube-test/ vs without AO http://futtta.be/wordpress/ru/blog/2015/05/07/youtube-test/?ao_noptimize=1) and can't reproduce I'm afraid.
If you have your site up & running somewhere, I'll be happy to have a quick look.
frank