I have a Samsung SME-2220 system. All four cameras that came with it are up and running. Two have night vision. We appear to have someone in the area who creeps around and shoots light at the cameras and manipulates the image on screen somehow. On screen at night I see spots of light or figures of light that move through the air in view of the cameras and during the day there may be an image of a bird that appears and erratically moves about or there will be a single spot or shadow that moves on the lens or image. These are wired cameras. How is it possible that these things can be projected, or however it is done, and appear on the cameras when they don't really exist? I use to have a cheap wireless camera that some of this happened with and I guess I could understand how the signal might be altered to affect the image.