Incoming call failed


My GrandStream UCM6510 is configured like this: Inbound => SIP Trunk (VoIP Trunk) => IVR => Queue.
Currently, it has the following issue:

  • When incoming call is made, no sound or ring plays
  • In the CDR, it shows that call is failed
  • The call does not reach to IVR yet
  • It happens many time in day, about 10% of total calls (total is around 1000 incoming calls/day)
  • I have checked the trunk provider, no issue from them

Please help me to fix this issue.

Thank you


You need to do a network capture and replicate the issue so that we can see the details of what happened to the call to cause the missed call issue. Does the caller hear anything when this occurs?