HellRaiser1st

hello everyone i just installed my cctv system last week and i have been having a problem with my cameras. the problem is that my night vision LED do not turn off during daylight they are always on, the light sensor is functioning properly as i see coloured video during day light and normal night vision during night time, the problem is that everyone who is dressed in black comes out purple during day light and my leds are always on and the cameras draw to much attention with 48 red led's. is there a way to turn them off ? my standalone dvr has no option for night vision on/off i don't know what to do, is it a problem with the cameras or i bought a crapy cheap useless dvr system ? here is the cameras i have bought: and here is the picture of the dvr i bought:

both cameras are the same on the bx for the cameras i only have CCD video camera written on it nothing else and at the back of the camera i have the qc sticker, pal sticker and thats it