It has nothing to do with the battery I can tell you that much, this has happened to myAM-F80 three times now. The first time it happened the unit was only a few weeks old, I took the unit back and the supplier tried two new batteries before finally sending it away to be repaired. It has just happened again for the third time, I would love to know what causes this. On the last (second) repair, was a reference to padding settings, and a repaired switch...does this mean anything to anyone??? It's a great player and recorder but sooooooo unreliable.