Garmin have released new firmware 4.2 for the Zumo, see Garmin website for details.
Changes from version 4.10 to version 4.20:
• Software update restores Bluetooth settings to default values. Bluetooth devices must be paired with the zumo again.
• Added the ability to reset the odometer map field.
• Increased Bluetooth volume when connected over A2DP.
• Improvements to screen brightness.
• Fixed crashes that occur when importing long routes from MapSource.
• Other general software improvements.
Changes from version 4.10 to version 4.20:
• Software update restores Bluetooth settings to default values. Bluetooth devices must be paired with the zumo again.
• Added the ability to reset the odometer map field.
• Increased Bluetooth volume when connected over A2DP.
• Improvements to screen brightness.
• Fixed crashes that occur when importing long routes from MapSource.
• Other general software improvements.



? As if .......
if not do one now and see if that cures it?