Hello, we have a Spectralink 8440 Phone and the newest Firmware 4.6.1J.0034. We connected succesfully the Phone to the Lync Server 2013 and it has had worked for 2 months. After 2 months the calls does not been forwaded to the phone anymore. The caller hears the ring sound, but the Phone does not ring or show a call on the display. The internal Lync calls to the phone are working. Can anyone please help us to solve the problem? Best regards mctech