HD playback not working

I’m trying to embed playlists of 720p HD video on my site and force them to play in HD using the vq=”hd720″ parameter, but it’s not working… I get 320p playback.

According to the documentation and this old post, the functionality was added in version 1.0.5 and I’m using 1.0.6 which is the latest.

https://wordpress.org/plugins/youlist/