The following procedure will clear the AT-900 internal memory and reload the factory settings:
(CAUTION!!!!: All USER information will be lost!!! Be sure to back up any information you wish to keep!!!)
1. Touch SYSTEM on the main screen.
2. Touch UTILITY.
3. Touch FACTORY RESET.
4. Touch OK
NOTE: Never turn off the power during a Factory Reset. This may result in corrupted internal data and may prevent the power from being turned on again.