I disabled every plug-in and reverted to the “out of the box” theme. It still kept resetting to Kubric. So, I picked another theme and I have not had a problem at all. I even tweaked the theme and am running all the plug-ins. So, if you have this problem try changing themes. There’s no rhyme or reason to it but changing themes seemed to work. For whatever reason the Zen 2.0 theme would not work for me but the Artsemerging theme by Nathanial Stern would.
Hope that helps a little.