The Unit runs very slow, and freezes often, more than 80 percent of the time.  

Sometimes when I turn it on I get an error that reads “USB open failure4” or “Enter the name of the driver for this USb device”

Other times if you turn it on and don’t get any type of error message as soon as you click on anything the device becomes unresponsive and the clock in the upper left hand corner of the screen stops.  Ive left it set like that for as loang as 5 hours and it never recovers.  

Things Ive tried……I have updated the SD card.  If I get an error, I have turned the unit off, removed the SD card and reinserted it, making sure it is fully seated.