From the horse's mouth; it's a software issue and it'll be fixed eventually in an update.
Thank you for emailing HTC Technical Support regarding the camera on your Evo 3D.
This is an issue that is currently already under review and will be addressed in a future software update and we do greatly appreciate your taking the time to make us aware of this matter.
We do apologize for any inconveniences that this may have caused, NeoteriX.
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