@Deerman
You could first try a simple reset. If that doesn't help, follow this:
All settings, user data*, and satellite data may be erased when resetting the GPS. User data can be backed up to the computer. For assistance, see the FAQ article "How do I back up user data from my outdoor GPS with a USB interface?" before performing the reset.

To perform the master reset:

  1. Turn off the Astro
  2. Press Map, Enter and Power simultaneously
  3. Wait for Astro to power on
  4. Release Power
  5. Wait for the message Do you really want to erase all user data?
  6. Release remaining buttons
  7. Select Yes


Astro 220 or 320 is now reset. Leave the device outside with a clear view of the sky for a minimum of 20 minutes to acquire satellite data.

*User data consists of waypoints, routes, tracks, and geocaches
Info from here:
Code:
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