'Add Media' and 'Text' view are unresponsive/broken in the page editor

Hi there,

I've already ran quite a few tests against other plugins and default themes. Here's where I'm at:
-2012 theme is active (was using Rehub theme before)
-marketpress plugin is active

As soon as I disable Marketpress the page editor functions correctly (both 'Add Media' and the 'text' editor when creating a page). See attached screenshot.

Please advise,
Thanks