I put in my trouble ticket a few weeks ago, and since taking my kindle out of the cover have had no freezes or reboots.
Amazon CS just called and offered me a full refund, plus a $25 promotional credit to upgrade to the lighted cover. I just promptly ordered one.
This time in burnt orange to make it harder to misplace - nothing like glancing in the back seat of a car or cab and not noticing you're leaving you kindle behind because the black cover blends in with the darkness.