To get the factory presets back, just follow these 4 steps:
1. Press the "UTILITY" button.
2. Now use the right arrow key to navigate to the "FILE" menu of the utilities.
3. Use the "ERASE ALL PRESETS" command by selecting "erase" under the "action" menu, setting the "include" parameter to "all presets" and then hit the "OK" button twice to execute the command.
4. After seeing "All user presets erased", just switch the unit off and on again and now all factory presets are restored.
5. Restart the Unit.