[Plugin: Video Thumbnails] theme based errors

so im having some difficulties getting the plugin to work with my theme, i am using https://github.com/retlehs/roots/wiki as my base theme, and then have been customising it for a number of weeks.

when i change my theme back to twenty11 the plugin works perfectly, but when i use the roots theme, i get the following errors:

youtube: We didn’t find a video thumbnail for this post. (be sure you have saved changes first) {NOTE: i have saved the changes first}

vimeo: Error retrieving video information from the URL http://vimeo.com/api/v2/video/39251390.php.
Libcurl error 6: Couldn’t resolve host ‘vimeo.com’. If opening that URL in your web browser returns anything else than an error page, the problem may be related to your web server and might be something your host administrator can solve.

can you offer any advise to me as to where i can go from here, i am too far into the development of my site to change the theme, maybe this is a permissions error somewhere on my server? i have checked the permissions on my assets media folder, and its set to 755

not sure what else i can do on this??

thanks in advance

http://wordpress.org/extend/plugins/video-thumbnails/