Problems occur with cat 5 cable when using up to 4 cameras on this cable when the distances are not equal i.e when the first camera installed is at 10 meters for example and the next camera is wired 20 meters further on and so on for the next two cameras. We generally install the cat 5 to a central point then "branch" off using rg59 to the cameras. This way the cat 5 lengths are equal.