Dennard Dome Earth Fault

Friday afternoon nightmare can anyone help.

Had to replace a two year old dennard 2060 dome due to the motor error 'bad end stop'. The replacement new 2060 dome works fine on the ground but when when it's mounted to the swan neck on top of the pole the picture goes haywire!

After checking connections, power and everthing it became evident that I now had an earth fault. But the old one always had a perfect picture. The power is supplied from a local source near the pole and the video is sent back to a DVR with a different power source again no problem for the old one.

After returning home I thought best to have a look at these two domes before I head off tomorrow morning. I meterd out the earth cables and found on the new dome the earth drain cable and the coax braid are shorted together inside the camera. This is where my problem lies, on the older dome the earth cable and the coax braid are seperate and would never cause a problem.

As I can't speak to DM until Monday can anyone tell me if they have come accross this before and is there anything I could do. I can't disconnect the earth at the pole because there are lights on it.