I have an older NightOwl system, and had a mixture of nightowl cams, and Zosi cams. Yes cheap, but they do the job. Over time, the night vision has almost depleted. All cameras I try, I can barely see anything. From outside, I can see the IR lights. They all run to a dvr via bnc and power. Can the DVR itself not be powering them correctly? Any help is appreciated.