I'm unfamiliar with the Cybook also, but while you're waiting for help, it might be a good idea to read some of the troubleshooting threads in the Cybook forum.
Gen3 Troubleshooting
Hardware- and software-related problems, bugs. solutions
I hope it's easily repaired and not expensive to do so but I'll let the experts chime in. You could also start a new thead in that forum and you may get help or information a bit faster.
WetDogEared