How are you connecting the nodes to it? If you are using the 4pin waterproof connector, check it for shorts or open connections. Some of these have had issues. The next step is to make sure that the hub doesn't have a blown fuse on that port. The third step would be to swap out the nodes connected to the non functioning unit with a string that is working and see what happens. Even though the dumb strings are much easier to debug than the smart strings, simple things can go wrong and shut down the entire string. If the 12 wire is broken or connected to the wrong pin, nothing on the string will work. The DSC may be setting up but if the string does not work, you will never see it.