I have some Siemens DECT sip handsets, which are cutting off on outbound calls after 30 seconds. Doesn't seem to affect other phones, or inbound calls.

I have tried setting the transport to TCP and adding {ignore_display_updates=true} to the bridge action but this hasn't helped.

What could it be?

2012-06-22 11:43:52.978442 [DEBUG] switch_core_session.c:923 Send signal sofia/internal/1002@192.168.1.1 [BREAK]
2012-06-22 11:43:52.978442 [DEBUG] switch_core_session.c:923 Send signal sofia/internal/1002@192.168.1.1 [BREAK]
2012-06-22 11:43:52.998446 [DEBUG] sofia.c:5838 Channel sofia/internal/1002@192.168.1.1 entering state [terminating][0]
2012-06-22 11:43:52.998446 [DEBUG] switch_channel.c:2899 (sofia/internal/1002@192.168.1.1) Callstate Change ACTIVE -> HANGUP
2012-06-22 11:43:52.998446 [NOTICE] sofia.c:6628 Hangup sofia/internal/1002@192.168.1.1 [CS_EXECUTE] [NORMAL_UNSPECIFIED]
2012-06-22 11:43:52.998446 [DEBUG] switch_channel.c:2922 Send signal sofia/internal/1002@192.168.1.1 [KILL]
2012-06-22 11:43:52.998446 [DEBUG] switch_core_session.c:1228 Send signal sofia/internal/1002@192.168.1.1 [BREAK]
2012-06-22 11:43:52.998446 [DEBUG] switch_ivr_bridge.c:588 BRIDGE THREAD DONE [sofia/internal/1002@192.168.1.1]
2012-06-22 11:43:52.998446 [DEBUG] switch_ivr_bridge.c:613 Send signal sofia/external/01234567890 [BREAK]
2012-06-22 11:43:53.018396 [DEBUG] switch_ivr_bridge.c:501 sofia/internal/1002@192.168.1.1 ending bridge by request from write function
2012-06-22 11:43:53.018396 [DEBUG] switch_ivr_bridge.c:588 BRIDGE THREAD DONE [sofia/external/01234567890]
2012-06-22 11:43:53.018396 [DEBUG] switch_ivr_bridge.c:613 Send signal sofia/internal/1002@192.168.1.1 [BREAK]
2012-06-22 11:43:53.018396 [DEBUG] switch_channel.c:2899 (sofia/external/01234567890) Callstate Change ACTIVE -> HANGUP
2012-06-22 11:43:53.018396 [NOTICE] switch_ivr_bridge.c:676 Hangup sofia/external/01234567890 [CS_EXCHANGE_MEDIA] [NORMAL_CLEARING]
2012-06-22 11:43:53.018396 [DEBUG] switch_channel.c:2922 Send signal sofia/external/01234567890 [KILL]
2012-06-22 11:43:53.018396 [DEBUG] switch_core_session.c:1228 Send signal sofia/external/01234567890 [BREAK]
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:443 (sofia/external/01234567890) State EXCHANGE_MEDIA going to sleep
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:385 (sofia/external/01234567890) Running State Change CS_HANGUP
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:625 (sofia/external/01234567890) State HANGUP
2012-06-22 11:43:53.018396 [DEBUG] mod_sofia.c:469 Channel sofia/external/01234567890 hanging up, cause: NORMAL_CLEARING
2012-06-22 11:43:53.018396 [DEBUG] mod_sofia.c:517 Sending BYE to sofia/external/01234567890
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:47 sofia/external/01234567890 Standard HANGUP, cause: NORMAL_CLEARING
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:625 (sofia/external/01234567890) State HANGUP going to sleep
2012-06-22 11:43:53.018396 [DEBUG] switch_ivr_bridge.c:1456 sofia/external/01234567890 skip receive message [UNBRIDGE] (channel is hungup already)
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:416 (sofia/external/01234567890) State Change CS_HANGUP -> CS_REPORTING
2012-06-22 11:43:53.018396 [DEBUG] switch_ivr_bridge.c:1459 sofia/internal/1002@192.168.1.1 skip receive message [UNBRIDGE] (channel is hungup already)
2012-06-22 11:43:53.018396 [DEBUG] switch_core_session.c:1228 Send signal sofia/external/01234567890 [BREAK]
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:385 (sofia/external/01234567890) Running State Change CS_REPORTING
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:685 (sofia/external/01234567890) State REPORTING
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:79 sofia/external/01234567890 Standard REPORTING, cause: NORMAL_CLEARING
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:685 (sofia/external/01234567890) State REPORTING going to sleep
2012-06-22 11:43:53.018396 [DEBUG] switch_core_session.c:2333 sofia/internal/1002@192.168.1.1 skip receive message [APPLICATION_EXEC_COMPLETE] (channel is hungup already)
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:440 (sofia/internal/1002@192.168.1.1) State EXECUTE going to sleep
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:385 (sofia/internal/1002@192.168.1.1) Running State Change CS_HANGUP
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:410 (sofia/external/01234567890) State Change CS_REPORTING -> CS_DESTROY
2012-06-22 11:43:53.018396 [DEBUG] switch_core_session.c:1228 Send signal sofia/external/01234567890 [BREAK]
2012-06-22 11:43:53.018396 [DEBUG] switch_core_session.c:1428 Session 45 (sofia/external/01234567890) Locked, Waiting on external entities
2012-06-22 11:43:53.018396 [NOTICE] switch_core_session.c:1446 Session 45 (sofia/external/01234567890) Ended
2012-06-22 11:43:53.018396 [NOTICE] switch_core_session.c:1448 Close Channel sofia/external/01234567890 [CS_DESTROY]
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:514 (sofia/external/01234567890) Callstate Change HANGUP -> DOWN
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:517 (sofia/external/01234567890) Running State Change CS_DESTROY
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:527 (sofia/external/01234567890) State DESTROY
2012-06-22 11:43:53.018396 [DEBUG] mod_sofia.c:374 sofia/external/01234567890 SOFIA DESTROY
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:86 sofia/external/01234567890 Standard DESTROY
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:527 (sofia/external/01234567890) State DESTROY going to sleep
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:625 (sofia/internal/1002@192.168.1.1) State HANGUP
2012-06-22 11:43:53.018396 [DEBUG] mod_sofia.c:469 Channel sofia/internal/1002@192.168.1.1 hanging up, cause: NORMAL_UNSPECIFIED
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:47 sofia/internal/1002@192.168.1.1 Standard HANGUP, cause: NORMAL_UNSPECIFIED
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:625 (sofia/internal/1002@192.168.1.1) State HANGUP going to sleep
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:416 (sofia/internal/1002@192.168.1.1) State Change CS_HANGUP -> CS_REPORTING
2012-06-22 11:43:53.018396 [DEBUG] switch_core_session.c:1228 Send signal sofia/internal/1002@192.168.1.1 [BREAK]
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:385 (sofia/internal/1002@192.168.1.1) Running State Change CS_REPORTING
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:685 (sofia/internal/1002@192.168.1.1) State REPORTING
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:79 sofia/internal/1002@192.168.1.1 Standard REPORTING, cause: NORMAL_UNSPECIFIED
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:685 (sofia/internal/1002@192.168.1.1) State REPORTING going to sleep
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:410 (sofia/internal/1002@192.168.1.1) State Change CS_REPORTING -> CS_DESTROY
2012-06-22 11:43:53.018396 [DEBUG] switch_core_session.c:1228 Send signal sofia/internal/1002@192.168.1.1 [BREAK]
2012-06-22 11:43:53.018396 [DEBUG] switch_core_session.c:1428 Session 44 (sofia/internal/1002@192.168.1.1) Locked, Waiting on external entities
2012-06-22 11:43:53.018396 [NOTICE] switch_core_session.c:1446 Session 44 (sofia/internal/1002@192.168.1.1) Ended
2012-06-22 11:43:53.018396 [NOTICE] switch_core_session.c:1448 Close Channel sofia/internal/1002@192.168.1.1 [CS_DESTROY]
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:514 (sofia/internal/1002@192.168.1.1) Callstate Change HANGUP -> DOWN
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:517 (sofia/internal/1002@192.168.1.1) Running State Change CS_DESTROY
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:527 (sofia/internal/1002@192.168.1.1) State DESTROY
2012-06-22 11:43:53.018396 [DEBUG] mod_sofia.c:374 sofia/internal/1002@192.168.1.1 SOFIA DESTROY
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:86 sofia/internal/1002@192.168.1.1 Standard DESTROY
2012-06-22 11:43:53.018396 [DEBUG] switch_core_state_machine.c:527 (sofia/internal/1002@192.168.1.1) State DESTROY going to sleep