HIkvision/Synology sudden bad pixellation issues

[nictry 0]

Hi, new to the forum and hoping some of the experts on here might be able to help me out?

 

I have had a Synology NAS DS116 hooked up to 4 Hikvision POE DS-2CD2042WD-I cameras for a while and recently started getting bad pixellation on 2 of the cameras. I thought one was down to age and perhaps just needed a replacement so bought a Hikvision IPC-B120

to replace it with which works perfectly for about 5 mins then goes horrendously pixelated even worse than the original camera. I have the cameras set up through CAT6 cable into a poe switch and then into a homeplug but along with these 2 there is another camera which works perfectly (same connection through a POE switch as the others) I have tried changing the cat 6 cable, tried another camera and the same issue occurs?

 

This has all worked fine for years so reallyy cant fathom why this is now a problem that seems impossible to fix. I ahve shown a screenshot to hopefully show how bad it is.

 

[nictry 0]

I have wondered if this could be down to a lack of power along the poe so have bouight a poe+ which allows for 30w instead of 15w per channel but if this doesnt work I really have no other ideas?

 

I have done some more testing and a fully working camera attached to the same cat6 cable but with the other 'currently' working camera still fails as soon as it is switched with the pixellated camera. In essence this means something has happened that has turned four fully functioning cameras into just one that works with the others pixellating within minutes of plugging in??????

[jeromephone 6]

Have you tested the cable