Incoming calls on external PSTN unexpectedly terminating

[Armo07]

3CX Phone System Version5.1.4128.0
XP Pro SP2
GrandStream 4104

Calls from external PSTN unexpectedly terminating on odd occasions, usually within 20 seconds.

Here's the log:

10:22:49.046 Call::Terminate [CM503008]: Call(57): Call is terminated
10:22:49.046 Call::Terminate [CM503008]: Call(57): Call is terminated
10:22:49.031 LineCfg::getInboundTarget [CM503011]: Inbound out-of-office hours' rule for LN:10003 forwards to DN:20
10:22:32.296 CallCtrl:nLegConnected [CM503007]: Call(57): Device joined: sip:[email protected]:5060
10:22:32.296 LineCfg::getInboundTarget [CM503011]: Inbound out-of-office hours' rule for LN:10003 forwards to DN:20
10:22:32.281 CallCtrl:nLegConnected [CM503007]: Call(57): Device joined: sip:[email protected]:5062
10:22:30.437 CallCtrl:nSelectRouteReq [CM503004]: Call(57): Calling: Ext:20@[Dev:sip:[email protected]:5060]
10:22:30.437 Line:rintEndpointInfo [CM505002]: Gateway:[GrandStream 2] Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [Grandstream GXW4104 (HW 0001, Ch:1) 1.0.0.55] Transport: [sip:192.168.1.104:5060]
10:22:30.437 LineCfg::getInboundTarget [CM503011]: Inbound out-of-office hours' rule for LN:10003 forwards to DN:20
10:22:30.437 CallCtrl:nIncomingCall [CM503001]: Call(57): Incoming call from unknown@(Ln.10003@GrandStream 2) to [sip:[email protected]:5060]
10:22:30.437 LineCfg::getInboundTarget [CM503011]: Inbound out-of-office hours' rule for LN:10003 forwards to DN:20


Any ideas appreciated.

Rgds,
Sam

 

[Nebula]

Check the call progress tone settings on the Grandstream gateway are correct for the region you are in.

 

[Armo07]

Check the call progress tone settings on the Grandstream gateway are correct for the region you are in.

I will check this, thank you. But I'm quite sure I got this right during set up.