Best thing to do with any apparent hardware fault is
1. Restart (you already tried that)
if that does not work
2. Backup data and perform a Security Wipe (Settings, Security, Security wipe) and set your playbook up again.
if that does not work
3. Debrick.
If debrick does not work, call your country's RIM support number ( www.blackberry.com/playbook )Tell them you have already reinstalled the OS using Desktop Software (because that is what they will walk you through otherwise) Depending in whether you are in warranty you will then have various repair/replace/trashcan options.
Debrick.
Backup your data the best way you know how.
Make sure you know your Blackberry ID and password
Turn Playbook right off (i.e. Shut Down til black)
Download latest Blackberry Desktop Software to your PC or Mac and start it up
The next bit happens very quickly.
Connect the Playbook by USB cable.
If the red light starts to glow or playbook starts up, press the Off button til it goes off.
Because Playbook is off you will get an error message basically saying Retry or Update (on Mac it may say Repair rather than Update)
Quickly select the Update (or Repair) option
The Playbook will start to get a new OS that will take al least an hour to download via the PC
Follow the registration process using your current Blackberry ID
Add back your email accounts etc.
Reinstall your apps from App World, My World.
