I was able to lick this problem with lots of time and CSS. Due to theme differences, my solution may not work for you. I wanted more control over the look and sizing, including an oversize full 1280 video window.
In part I had problems because the videos from vimeo live inside iframe with their own CSS we cannot touch.
56.25% is the height relative at width to produce an HD aspect ratio.
Next time around I may just make a custom Vimeography theme by copying and editing one.
This problem got fixed creating other gallery with a different theme. Feels bad anyway.
thanks!
Hey, this bug was introduced by a change with Vimeo’s player and has since been corrected in the core plugin. Try updating to the latest version and let me know if it works for you!