VGA Interference

So we have a splitter coming straight from a mac pro 3.1 (I don't own this, the place does) but for some reason there seems to be interference from audio. We have a sound deck right beside the computer setup and whenever someone talks or plays music through the mics the image on all the displays connected to the spliiter goes a little blurry/wavvy/fuzzy whatever you want to call it. The vga splitters are powered, they aren't passive so that's not the problem. Is there any way of fixing this. I know vga is an old technology but if we want to go to dvi we have to get new projectors, monitors, splitters etc.