I have the same issue.
Some time ago, my friend got a mail from Tom Tom, that there was a change in the coordinate-systems and that there were software changes required in order to get the TomTom work correctly after this change. Something about a leap second... so as far as i know right now: there needs to be a change made by some software to be made.
but i don't know if it's the firmware of the logger or the program with which i try to load the data from the logger that needs to be changed. Sadly, as far as i know, right now, no updates for any component for my logger is available. I hope for a solution very soon!!