Cox Contour & Xbox One

I recently upgraded to Contour service with the Cisco 9865DHC 6 DVR. When it was originally connected by the tech, it was passing through my Xbox one correctly. Once the box was activated however, I only get a black screen when going to the TV app. When I disconnect the cable box, the xbox states that the cable box is disconnected, so there is definitely a signal coming from it. I've varied the order that I power on the devices and messed around with the various display settings to no avail. Does anyone else have an idea?