Hi,
As i told you i had changed the power supply and now the coloured lines have stopped but the night vision is clear only when i connect two cameras. But when i connect more than two 1 or 2 cameras will give me clear picture where as the other two will have a blurred picture. Also sometimes the picture keeps switching on and off. Now i have read in this forum that it is because of power supply. But i have used the same power supply elsewhere with 4 cameras and it is working fine. Why not here. As i told you the longest cable is 15mtrs.