we have a relatively small church and we use video projection for the words to songs and sermon notes, etc. we have a main seating area and two additional seating areas on left and right side of the main area. we have a projector in each of the seating areas as well as one on the back wall as a confidence monitor for singers on stage.
from the projection booth in the back of the main seating area, the signal is run through a Kramer VP-719DS switcher. the signal from the computer to the VP-719DS is DVI. from the VP-719DS the signal is VGA.
right after the VP-719DS in the video projection booth is a 1x5 VGA distribution Amp. one output on this unit goes to the video recording booth upstairs (there converted to composite video to mix in with video from 2 cameras). another output goes to the projector for the back wall, and then 2 outputs going to the overflow area projectors on the right and left sides. the 2 overflow and the back projector have VGA from the booth to each projector. then the signal to the front area is converted to HDMI then sent to the front via Cat-6 for the 120 foot travel and back to HDMI & then goes through a 1x2 Kramer HDMI Distribution Amp. this feeds 2 projectors, one for each side of the front area, above the stage.
now the problem.................
every now & then and totally random (as far as we can tell) one or more of the projectors will go blank and then reappear in about the same time it takes to read this. we don't see it on the projectors in the overflow areas because as soon as the preacher starts the sermon, we switch to the video camera feed (so overflow people can see the Pastor). that is a whole different line and input for the projectors.
we notice this on the back and the front 2 projectors. some times simultaneously and some times individually. even though the front 2 projectors get the same single HDMI via Cat-6, some times only one will go blank. and which one is variable and random.
I realize this is long, but wanted to try to give enough info to make a determination. however, if there is more info needed, let me know and I will do my best to provide it.