Screen flickering / flashing

[paulrvernon@gmail.com]

My Nook Simple Touch screen has just started to flash / flicker after it gets passed the "Your Nook is starting up..." screen and reaches the screensaver. I can get to the Home screen by swiping and I can get to the library but it looks empty / isn't seeing anything. Does anyone have any ideas? I've tried turning off / on etc.

Thanks, Paul.