Check if the camera settings have not been changed. Be aware that VideoRay Pro 4 does not use the same defaults as the camera manufacturer's Factory Default settings. For VideoRay Pro 4 the Lens Type must be set to "ELC," and the DSS must be set to "1X." To quickly restore the camera to the recommended VideoRay Pro 4 camera menu default settings, first restore the camera's factory default settings, and then change the Lens Type to "ELC" in the Lens sub-menu, and change the DSS setting to "1X" in the Exposure sub-menu.
See http://download.videoray.com/documentation/v1_3_1/pro4/html/menu_camera.html for more information.
If the problem is video noise, it may be caused by a ground issue. If there is a difference in ground potential between the power source and the water, this can introduce video noise. It is similar to hum in an audio system when there is ground problem between components. In order to eliminate the video noise, install the ground lift adapter between the power cord and control panel.