mfalco

I am hoping someone could help me..... I have a digiplex 440, about half of my cameras went out all at one time. They are up on the DVR's, and I can control them but they will not appear on my call up monitors... I have tried a soft reset, completely disconnected the power and replaced the surge protectors and still nothing. The digiplex is working and powered on, and the other half of the cameras are working fine and come up on my call up monitors. Any suggestions??