Settings are blank after receiving a call while tethering

When I am tethering and I receive an incoming call, the tethering stops. I used to have to go to my settings , and put tethering back on. After having upgraded to version 4.1, when after a call I want to go to my settings, I just get a blank screen. Have to restart the phone to be able to open my settings, and put the tethering back on.
Very irritating, Apple please solve this in the next update.