UPDATE::

I've been in touch with Tom Tom Support and had the following, which didn't work and still gave me the screen freeze/reboot at the set time setting.
Might be of use to someone?:--


This issue can be caused due to some corruption in the application software.

We need to remove the application first and then reinstall a new application via TomTom HOME.

To do this please follow the steps mentioned below:

STEP 1 - Backing up your TomTom device.

- Click ‘Manage my device’ in TomTom HOME and select the ‘Items on device’ tab
- Select ‘Maps’ and ‘Postcodes’
- Click ‘Copy items to computer’
- Close HOME

STEP 2 - Delete the Application from device

- Connect the device to the computer and open TomTom HOME
- Go to Manage My Device
- Click 'Items on my device'
- Select the 'Application' and click 'Remove items from device'

STEP 3 - Delete the Applications from the computer

- Go to Manage My Device
- Click 'Items on computer'
- Select the 'Applications' (there may be more than one)
- Click 'Remove items from computer'

STEP 4- Check the device memory for errors:

Windows:
- Click Start > (My) Computer > right-click on the icon for the TomTom device
- Click Properties >Tools tab.
- Under Error checking click Check Now. Tick both boxes and then click Start

Mac:
- Go to Applications : Utilities : Disk Utility
- Select the device / memory card in the left pane and then click Repair Disk

STEP 5 - Re-download the Application

- Go to Update My Device
- Select the 'Application' (it may be pre-selected)
- Click on Update and install
- Repeat this process until no more applications are offered.

I look forward to hearing from you soon.

Please let me know have you made any progress or not.

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