Admin menu order drags to bottom of page

I’m experiencing a problem with the admin interface and rearranging menu items in a custom menu.

The problem:

When attempting to drag a second-level menu item lower in the sub-menu the page scrolls to the bottom, not allowing any control of where the navigation item is placed. It sees to always be restricted to the third-level and is indented without intention when the page scrolls to the bottom.

I have disabled all plugins, and had no results change.
Changing the theme to default 2013 and disabling plugins did restore the regular functionality of the admin menu drag and drop.

There were no javascript errors on the page when inspecting with Firebug. Would like to not have to switch themes every time the navigation needs to be rearranged.

Is there a fix for this problem? How might I diagnose what’s wrong with the theme and could you please offer a recommended solution. Thank you kindly.