Contour Record6 DVR defects

I’ve had about 5 Contour Record6 DVRs over the past several years and all of them have had playback problems related to fast forward and reverse. These problems include shooting back to the start of a recording or shooting forward to the end. The problem most often to occur is during fast forward when the very beginning of the program would play instead of the intended return point. I am able go back to somewhere near the intended return point by pressing fast forward and play again but sometimes return past that point. It seems that all replacement DVR boxes are old equipment and I am just replacing one defective box with another equally defective box. Is there any way to get a Record6 DVR that works properly?