My answer was based on the model numbers you originally gave. If you have the DRS4DNXT then it isn't software of the dome. The software of the DRS4DNXT hasn't changed since we have started selling it. If you ever do need to check the software of the unit or attached devices, it is shown in the Sensor List under initial setup of the menu.
What is the version number of your TZT2? Did you factory clear the unit after it was updated?