Can anyone help me, I have had a 2 camera system with 500gb DVR on my house for around 2 and ahalf years, the old DVR started making a grinding sound which got louder and louder so I gave in and bought a new one, so I thought it would be a straight forward swap over. This morning unplugged the old DVR and replaced it with the new one. Then to my horror the feed from the cameras was not coming through, so unplugged the new one and plugged in the old one again to check the camera feed, and now no camera feed on either. CAN ANYONE HELP ME?