Even though the cameras should be default it is always a good idea, with odd issues such as this, to log directly into the camera and default the image settings, and then also default the entire camera under the system settings.
Other than that, we really would need access to asses this type of issue. I understand in some applications thats easier said than dopne, but maybe you can take one of the problem cameras to a different location, and if we find the solution you will know what to do with the remaining cameras to fix them.