To reset the unit to factory defaults please do the following: 

•Navigate to Settings the the app drawer (should be on the second page) 

•Scroll all the way down to System Information

•Scroll all the way down to Reset to Factory Defaults. 

It will prompt you stating it will restart in two minutes. After pressing okay, please be patient and wait, It may appear it's not doing anything, but after two minutes the unit should restart and most likely show the SRT logo.