I control my dvr from my pc and view my cameras from my pc and a monitor. As of yesterday I am only able to view my cameras live and when I'm on my pc to rewind, the screen goes black and unable to see cameras but if I walk to the other room I can view it on the monitor and I can watch the cameras rewind. I had my wife try this on her pc in a different state and the same thing happens,she's able to view it live but when she rewinds she sees nothing on her pc, and I"m watching at the same time and see nothing on my pc but when I walk to the monitor I see it rewinding. To test my pc I loged into my friends dvr to see if I can control his cameras and view them with back data and I was able to. My question is what is wrong and what do I need to do with this dvr????