I'm hoping to make things easier for someone by this post. A couple things regarding the Zmodo H9104V and four cameras.
One thing they don't mention in the manual is that to wake up the DVR you must press "zero" on the remote. It goes to sleep a few minutes after you log out of it. It took me a couple hours of flailing to find this out.
If you're thinking of doing wireless cameras, it is a must to stay away from RF sources; network circuitry, PCs, transceivers and antennas, noisy electronic circuitry such as garage door openers, cfl bulbs,electric motors. My house is a wasteland of RF noise, so when I first tried the wireless setup I bought at Rural King, there was so much hash on the video that it took me only a few seconds to decide on wired cams. Though it was more work, obviously, I'm glad I did.
Considering you do go with the wired cams, just a few tips here; Running the video cables, try to keep from running directly adjacent to (within 2 or 3 feet) of existing electrical or signal cabling. Anywhere you can, run across, not in line with these noisemakers. By the way, I ran into three cams that within a few weeks, developed horizontal interference lines. Swapping out those cameras, indicated that the problem was a lack of noise filtering in the cameras themselves. I swapped them out for some Swanns from Wally World and they worked perfectly, with more leds, too.
Being able to block out some areas in the cameras' field of vision is a nice feature. Mine are setup for motion only and things like a shadow of a flag waving can be blocked out. Handy.
Also, I used a ferrite core on the main cable coming in from the cams, which helped cut down interference a little more. Hope there was something beneficial to someone here.