If your DVR cuts off the end of a program, this is due to a delay in processing the signal through the cable system. By the time the signal arrives at your home, if a show ends right at the top (or bottom) of the hour and your DVR clock doesn't account for that delay (which most don't) then it will stop recording too soon. You can fix this problem by adding time to the end of the recording to compensate for the extra seconds that are being lost in transmission.