Can't change background in sections

I am using the video background for the banner in Onetone, but when I go to change the other background images, such as Contact and About, instead of loading the new pictures, the theme is loading part of the video! And I can’t even change it back!

Help! There has to be a cure. If not, would it be cured by doing a fresh WP install? The site is brand new so it would not be that hard to do. Thanks!!