For more than a year now I have been using 2 batteries since the life is so poor on the OEM battery. Every 1 to 2 days I switch my drained battery out for a fully charged one and I drop the other in the charger. This has worked great for me up until a few days ago. Now every time I switch my battery the time and date reset to January 1, 2007 12:01 AM. Anyone have any idea why this may be happening? It never happened before recently.