No Audio or One Way Audio after Transfer or Forwarding


  • When you perform the attended-transfer(particularly the SIP REFER method)  by the transfer button on the IP phone for the incoming call. After the transfer of the call, it would have the one-way audio or no audio on both sides for the caller and the transfer target party.
  • The incoming call is forwarded by the extension always forwarding settings.
  • This article also applies to the situation with the calls via SIP trunk become no audio after a specific time like 15 mins.


1. Try to disable the Allow RTP Re-Invite option in the SIP Advanced setting.


2. Try to disable the Jitter Buffer for the trunk that involves the forwarding or transfer.



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  • 0

    This article also applies to the situation with no audio after PBX receives a Re-INVITE from the SIP trunk or external SIP device.

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