[Plugin: Viper's Video Quicktags] YouTube shows image in Excerpt

I’m using Viper’s Video Quicktags to show YouTube and Vimeo movies in my posts.

I’ve added add_filter( 'get_the_excerpt', 'do_shortcode', 11 ); to my functions.php and this seems to do the trick for Vimeo movies, but YouTube shows an image with a link, instead of the movie.

I’ve disabled all of my other plugins, but still no luck.

Any suggestions how i can fix this problem?

An example can be seen here:
https://basicgoodness.com/2010/tag/viper007bond/