Chosen Solution
My drift Stealth 2 has a reddish blurry mark with 2 light lines top right hand corner when recording - I cleaned the lens - red is lighter but still a bit blurry - why??
JJ Nel sounds like a damaged light/UV sensor For that you would have to get into the lens assembly and replace the sensor. Problem is that there is not guide as of yet and not even sure if you can get replacement parts.