Guys thank you very much! Yes it was the spot monitor on the DVR. I deselected cam 234 to NONE and left cam 1 on. I also adjusted the dwell time to zero. Excellent stuff!. This now explains how it was coming on for 5 seconds then going blank for 15 second as it was going through the 4 channels !!!. I hope this helps someone else here on the forum. Starfall