Pixelated/Randomly losing the main stream- from my Hikvision IP cameras?

[Newtothis]

OK, after updating and a simple restore, the problem remains. After updating, the live view was perfect for about 12 hours but then started to deteriorate over time. Starting with what looks like a soft, out of focus trail behind moving objects, turning into a blocky/pixelated trail and even seeing the same car/person on the screen in two different places. It only happens to moving objects and happens on both cameras. The only thing that improves the video is power off for a short while but after powering back on, the video starts to deteriorate over time again. Also, lowering the cameras resolution gives better live view.

 

[Newtothis]

Just another Update. Yesterday, I lowered both camera substreams fps to 10 and since then, the mainstream Live view has been excellent. Its as if the NVR is struggling to cope. Lowering the camera resolution also helps (there at full resolution now). Anyway, I will keep check.

 

[Newtothis]

Since lowering the substream fps on both cameras, the mainstream live view has been perfect. Would the NVR, (DS-7604NI-K1(B)), normally have problems with 2 cameras at full FPS on main and sub stream?