I have a Merlin magix system with 1 DSS 4450 hooked up to a 4424LD+. The extensions work when you press the buttons on the DSS, but the only light(green) on the DSS is the page button. The button lights stopped working after we had a phone tech come out and work on the system. He said it wasnt his fault so I have replaced the phone and DSS (including power supply) and the lights are still not coming up. Is there a way to turn this back on?