We have had phone service through them for years. Including Directv. All of a sudden. When a call comes in. It answers to the sound of a fax machine? We do not have a fax machine. Charter tech. came out and checked the lines. Even the phone modem. All checked out fine. We use the caller id on the tv. Nice little feature. Any ways. Once he unplugged it. It works fine. He even made sure the jack was working properly. But, once plugged back in for Directv caller id to work. We get the fax sound and only 1 ring. Strangest thing ever. It has been working fine for years. 2 things I can think of. The latest HR24 firmware is not compatible? Or the cable company pushed new firmware on the telephone modem that might not work with Directv? Any idea?