Not sure if this will work, but you could try factory resetting the unit, leave the cables unplugged as you have now, delete the unit from CUCM and re-add it as a CTS-1000?
Also I can't remember exactly how a CTS-1300 is connected, but is there an ACU between the codec and the cameras + mics? If so, try bypassing it and plug the camera + mic straight into the codec when you perform the above procedure.