Cameras Wont Switch On Vanguard

[cwilliams]

I have one transceiver module, one video receiver and four cameras. They use to switch when I clicked the camera numbers on vanguard but all of a sudden they now don't. Only one camera shows. All cameras are on units 1-4 and on vanguard when I click on a camera number it does not switch it only stays on one camera and when I move the video receiver around it picks up another camera but still only has one camera on the screen. Do you think I should get 3 more transceivers  (TM751) and 2 more video receivers (VR36A) or is there another way to fix this since it worked fine before.

[hawk1]

Since it worked before I would start looking for something that is plugged in creating noise on the powerlines.  Like a cell phone charger, laptop.  It sounds like to me that one camera is not turning off when it should.  Do you here your tm751 click when you try to change cameras?  If not then it might be that it is not getting the rf signal from the cm19.  I assume that is what you have.