I have a user assigned to a 6408. The user has complained of intermittent problems including, phone won't realease a call, can't answer a call, no dial tone when hand set is picked up - user has to hit the switch hook a few times to get dial tone, can't see time and date. I have tried the following steps: replace phone and cord to jack, deleted phone from programming and rebuilt, changed ports (to a different card), re-cross-connected in the wiring closet, tried both the blue/white and the orange/white pair on the jack, TTIed the phone on the neighbors jack. When the problem first started, she had a 6416 phone, but programming stated a 6408. Any suggestions?