One of my 622s has developed a new problem. It turns on ok and gets a signal. When I go to the menu and press #4 multimedia to transfer movies from the internal hard drive to the external hard drive, the unit locks up. After a minute or two the video goes black and the unit turns off. A power plug reset will get the unit back up and running, but the unit still locks up on menu item 4. Neither the remote nor the buttons on the front of the 622 will work. Has anyone else experienced this problem?