This is going to drive me nuts, and it's a short trip! I've got a ACS rel 4, with partner mail, cabinet is full. Extension 30 is blinking on the console and other phones where it is programmed as a dss button. The phone works, it just causes the dss button to blink. We have replace the 308 card, changed the phone, the jack and the wiring. It goes away when we change things, but starts blinking in about 2 days. Last step is to change the processor but I'm resisting.