what is better camera for the zoom low light scz-3430n

Hello

I have scz-3430n samsung cctv camera ,

is that on the market any better camera than this i can look for ?

I need more optical zoom this one is 43 x wdr zoom camera.

I also have some problem with the camera as is only black and white ,

and when i connect it to dvr 3/4 picture is ok but 1/4 is flashing picture

from the other cameras from the dvr

and it is only flashing when i connect this camera , others have no issue .

I change ports and cables and nothing better .

I am happy from the soft of dvr EDRHD4H4 , is dvd record and have internal

psu , and it work on 4 hd-sdi and 4 analogue cameras making 8 channels.

I am looking for similar or better dvr for more than 8 channels similar or better quality .

1 have you any idea of better zoom camera color at night and more zoom ?

2 is the camera samsung scz-3430n faulty?

3 better dvr than this what I have already ? EDRHD4H4