Callback Failure when using SIP Trunk on S-Series


For example, if your callback target caller ID is 11111222223.

1 - If the SIP trunk used for Callback is Register-Type.

The From and To header would be the same number "11111222223".

2 - If the SIP trunk used for Callback is Peer-Type.

PBX would use "callback+target caller ID" in From URI of the INVITE packet to make callback calls.

See the following figure of the INVITE packet sample includes of the issue:


And when you check the CDR, you would find the Call From of the call log would be like "Callback11111222223".



  • If your are using Register-Type SIP trunk, make sure the Fromuser field has been filled with the correct value. Usually it is same as the Username field.
  • If you are using the Peer-Type SIP trunk, make sure the Global DOD has been configured, and upgrade the firmware version this temporary version: FW for Callback Issue Fix

We would fix this issue for Peer-Type SIP trunk in version 30.11.0.X. Stay tuned with the release note.

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