Samsung HT-X70 DVD player

Question

When playing a DVD, the dark scenes "flicker" between dark and VERY dark. It is almost muted at times. This does not happen to the digital cable system which is run as an HDMI pass through the unit so I know it is not the cable signal or the Sharp Aquos HDTV. It only happens when there is a DVD playing. The light scenes are fine. Any ideas?