I would be checking RMA status on those. I know in this country (Australia), they come with a 3 years RTB warranty.
I have sold a few of those Toshiba Tablet PCs, and most of the customers that I have sold them to have had one problem or another.
Blind Spots being on of them.
The other problem was the display would have a mind of it's own. For no reason, the display would turn 90 to 180 degrees.
Hmmmm.... Tablet PCs.... another bit of technology that I would wait for people to delevop a bit more.