[Jeff Hail]

Dave,
Looks like an older Lorex model. Each transmitter/ receiver uses an A and V signal. These are normally user defined. If A is audio and it is switched to video the weather channel gives you snow and no sound. Also if the switcher is not setup you then have to hunt for a channel it defaults to. This is done thru the setup button which should scan any active signals and lock them in. Are there any DIP switch's on the wireless transmitter? The older units when multiple camera's are used need to have channels assigned otherwise all camera's broadcast on the same signal input and cancel each other out.