First, ensure the duct smoke detector is powered properly and that all connections are secure. Check the airflow through the duct to make sure it’s within the detector’s specified range. Verify that the detector’s sampling tube is installed correctly and free from any obstructions. If the issue persists, try resetting the detector and reprogramming it according to the manufacturer’s instructions. If these steps don’t resolve the problem, it might be a faulty detector, and you may need to contact Silent Knight technical support for further assistance.