Okay so far I have found out that all installs with the AF dome have lines (plenty noise) in the image when zooming in and out, whatever is causing that also likely causes the black bar rolling up and down the image.
I have found out that it does not occur when powered from a single plug in adapter (5A tested so far, will test others).
This happens with both the 2014 and 2015 AF dome firmwares.
So it seems like either the distributed power supply does not have enough power to run these cameras, or the cameras are not grounded properly and get some sort of interference from the other cameras or even the PSU.
I have used fused power supplies as well as the PTC ones, 10A ones with 1.1 Amps each output for example - same issue regardless.
It can be a very noticeable black bar in some cases - it goes up and down the image over a period of time, sometimes going away completely for a while.
These cameras are not touching metal or anything, these can be as simple as sheetrock screws in a sheetrock ceiling, or in wood, or using plastic plugs.
Any suggestions? Without using single power supplies ofcourse 😀
That could get expensive.