Hi all, Thanks for your kind feedback. I am actually using 2 Energizer lithium AA batteries with the external battery pack. I'm guessing very likely, it's either the electrical connections from the battery pack to the player are getting old & corroded or the parts are wearing out and need more current to operate. I shall get it checked out by a Sony service centre. Still works marvelously by the way, which is why I'm reluctant to replace it. Cheers...