I have put 4 cameras at a checkpoint all within 20 feet of poe switch they are hikvision domes and are 6 mp each. The issue is for no reason one or two randomly will drop of switch and i can see it loose connection on switch locally. i have disconnected the fiber to main recording site until i solve present problem. I have tried a different switch and changed rj45 connectors on cable thinking it was a bad crimp,but not the case. The 4 cameras will connect after mutiple retries on disconnect from switch and finally will hold for couple of minutes. Its on a cisco switch now with fiber gbic for remote monitor and record. I have tried a inaxys which i use faithfully for some time,same results. I have some of these 6mp hiks at different site with no issue. Spoke with tech assist and they could only offer turn down resolution as i could be over taxing switch. I will try it tomorrow but im kinda skeptical.