Black flashes while watching dvds?

Every time that I watch a DVD using my 5 disc dvd changer that is part of my surround sound system, a black flash come across my screen about once a minute. The sound continues to play through the black flash, and the video doesn't lag afterwords, but the flash is pretty annoying and lasts about a full second. Sometimes, some lighter pixels (white and green mostly) that are in the shape of images on the screen will flash right before the black flash. Does anyone know what the cause of this issue is and if there is a way to fix it. I already tried getting a new HDMI cable, but it didn't change anything.