uatuba

I have installed a 16 channel DVR with 15 of the basic Zmodo cameras. On a number, there are major flickering and horizontal line problems. The reason I say "a number" instead of giving the exact count is that the problem is not consistent by channel. I can unplug/replug the AC adapter into the BNC cable and the channel may start displaying the picture clearly. Thinking that the problem may be interference from fluorescent lights, I ordered shielded Cat5e and some baluns. I made sure all of the cable was at least two feet from all of those fixtures, hooked everything up, and it still made no difference. I have swapped out the cameras, the cables, and tested the channels on the DVR with multiple cameras (all of the channels are working). It seems like a power issue, but I have no idea what the issue may be. Does anyone have any ideas? Thanks!

Thanks for the tips. There are two power adapters for the 16 cameras. Each is split into 8 ends. The cable runs are not very long (60' is the longest, 10' is the shortest and that run has this problem as well). I have tried plugging in just one camera, for example, and the problem doesn't resolve. If this were a ground loop issue, what would I do to resolve it?