Upgrade Archos 2oc

[dobking]

i got my archos 2oc for about a week and was quite happy with it before the moment when i found out that the auto shut off option didnt work properly - its allways set on default 10 minutes after restart.
so i though that upgrade software version might help, but when i select upgrade function and YES then plug usb cable like it said, player look like shuts off and didnt respond. computer cant see the device too. only after reset player work again.
current version is 2.48. is there any suggestions how to upgrade this device?