Season's Greetings Lucy I too have same phone with serial # 14018680 that has simular issue. It will receive data on head set, but you are not able to talk with any one for more than a few moments. Battery is new, and unit is like brand new. I left base unit un plugged for 1 day, and the plugged back in power unit. Head set would work once again, but only for a couple of hours, untill the base unit warmed up. I then placed base unit in refrigerator over night, and next day tried phone again. The head set worked perfectly for about 2 days, then same issue. Have you let your unit be un plugged for over night and tried to use the next day? I suspect issue with chip inside base unit.
Ted, December 2007