Could you email us a screenshot to firstname.lastname@example.org?
If you are operating in low-light and high frames/s, this is normal if the auto gain gets cranked up to the max. You should then reduce framerate to allow for some more exposure time, or use brighter lights in the environment where you use JeVois. See: http://jevois.org/doc/UserLighting.html
But it is also possible that your sensor has gone bad or that the connector for the sensor is loose somehow. In such case, we will ship you a new unit right away once we see the screenshot. We have had a few such cases (but fewer than 1 in 1000).