Digitizer dies when battery under 9% (iOS 7 beta 2)

A few days ago, my iPhone's digitizer stopped working. I have a white iPhone, 16 gig model. As it stopped working, the physical buttons were still functional, thus I was able to see that my battery was only at 5%. As I charged it, it suddenly started working. Now yesterday, the same happened, but at 9%. Does anyone have any experiences like that? As I searched through the Internet, there was no help to be found. And actually, I am now running iOS 7 beta 2, if that matters.