I had this very same problem when I flashed my N9 first time. I solved it by enabling the GPS from Phone settings. I had manually disabled GPS. Every time I started the camera app, it'd try to enable GPS for geo tagging and would fail, which I guess resulted in the not responding error. Later on, I'd enable GPS, open camera app and then disable geo tagging first. I would then proceed to manually disabling GPS from phone setttings.