The speaker in my Coby 7042 is loose and I need to replace the unit. Went to Brandsmart and the CSE didn't want to replace my tablet because he found is rooted. Is there any way to revert the root process and set it back to the stock ROM? As any other Generation 3 the unit is still under warranty and I don't want to open it to fix the problem. if not possible, can anyone explain me how to brick the tablet and make it impossible to turn on?