My BookPort dies after about 2 hours or less of use. Nothing works -- the buttons do not do anything and when I plug it into the computer, the BookPort Transfer software doesn't recognize it as being connected. In the past when this happened, I could solve the problem by removing the batteries for a minute or two. But now, the batteries have to remain out of the machine for about 12 hours. After that, I reinsert the batteries and the machine returns to life for an hour or so. I had sent the unit to the APH but since I sent it without the batteries inserted, the machine worked fine, When I got it back home, it worked for an hour or so, and the problem started up again. Any suggestions?