Video not widescreen - black bars added to L and R

My Vimeo video is not widescreen, but Video Filter is adding black bars to the left and right of the embedded video.

I have the default width & height settings at 480x320 and have also added those width and height parameters to the url, but the player is appearing as 480x270 with a video screen size of 365x270.
How can I get rid of the black bars?
Thanks
Gina