I have the same problem on my 4S...
As a temporary fix, I kill off the app [iOS 7+...double click the home key; swipe waze up] and relaunch.
I repeat as often as is needed
As a temporary fix, I kill off the app [iOS 7+...double click the home key; swipe waze up] and relaunch.
I repeat as often as is needed
Re: my screen goes black or dim (iOS)