Recently we added some DVR's to a CCTV analog system that was a straight live feed. The Tech has a multiplexer and a distributor amp at the camera location views are perfect; However at about approx. 1500 feet away are the DVR's located and all views are distorted. Cables from the camera go through a man-hole using RG11. If tested individually through monitor tester the views are perfect at DVR location. But when plugged into DVR with all other cameras is when all views are distorted. Any ideas?