Maybe its software as you say peterson.
Since I rooted my amazon I didn't install any software aside the recommended recovery app and usbnet
could it be that usbnet prevent kindle from sleeping while working in wireless mode? could it be that amazon wanted to (ab)use the super slow wireless to update itself?
Whatever the reason is my script solved it for me, and I no longer have to wake up at night to check if I turned my wireless off or not.
If in the future you got that annoying problem I am having, you know what to do
