Screen Brightness on iphone 4s
My iphone 4s has had a problem after i upgraded to ios 6 , the screen can be at one moment fully readable with the adjustment on brightness set to the middle ,,and then its light is off , checking the brightness its reset itself to no brightness , this happens with the auto switched on or off , i have hard reset the iphone , used itunes to do a restore and have set it up as a new iphone but the problem will not go away. Even on the charger i have the brightness set to mid way and when i take the phone off the charger the brightness bar moves to no brightness , i have one time had the screen on the brightness settings and watched the brightness bar lower to no brightness , this is with the auto brightness option switched off , this also happens with the auto brightness switched on as well.
All these problems happened after upgrading to ios 6 , the one thing i did notice after the first upgrade was the screen itself had a higher brightness than before , now the phone mostly sits at home as i cannot use the iphone as the screen brightness changes so much its become a pain to use , so i have to use my wifes samsung galaxy s3 , any ideas on how to sort this problem out or is it a trip to the apple store to get a new iphone 4s ?