Can't send faxes

[Alexord]

Hi,

I use 3 different providers that claim to support T.38 but with all of them I unable to send faxes
either I got error "No RTP packets were received" or "400 Bad Request".
One of providers lets to choose fax mode T.38 or transparent. Neither works with the same error "no rtp packets.."

From a provider's support I received this:

> We need 3CX to initiate a G.711 call and then send a reinvite on T.38.
> We are not that familiar with 3CX are you able to ask 3CX support if this is possible?

Is it possible to configure lake that?

Please, give me a hint! I've spent 3 working days on this, and have no idea any more

Some logs:

11:56:49.311 MediaServerReporting::RTPReceiver [MS105000] C:324.1: No RTP packets were received:remoteAddr=192.168.0.200:10038,extAddr=0.0.0.0:0,localAddr=127.0.0.1:7012
11:56:49.311 Call::Terminate [CM503008]: Call(324): Call is terminated
11:56:49.295 Call::Terminate [CM503008]: Call(324): Call is terminated
11:56:49.202 CallCtrl:nLegConnected [CM503007]: Call(324): Device joined: sip:[email protected]:5060
11:56:49.202 CallCtrl:nLegConnected [CM503007]: Call(324): Device joined: sip:[email protected]:5100;user=phone
11:56:08.734 Line:rintEndpointInfo [CM505003]: Provider:[Gafachi] Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [] Transport: [sip:192.168.0.200:5060]
11:56:08.734 CallCtrl:nAnsweredCall [CM503002]: Call(324): Alerting sip:[email protected]:5060
11:56:05.843 CallCtrl:nSelectRouteReq [CM503004]: Call(324): Calling: VoIPline:0078123200031@(Ln.10011@Gafachi)@[Dev:sip:[email protected]:5060]
11:56:05.812 CallCtrl:nSelectRouteReq [CM503010]: Making route(s) to [sip:[email protected]:5060;user=phone]
11:56:05.812 CallCtrl:nIncomingCall [CM503001]: Call(324): Incoming call from Fax.888 to [sip:[email protected]:5060;user=phone]

------------------------

16:34:35.811 Call::Terminate [CM503008]: Call(237): Call is terminated
16:34:35.811 Call::RouteFailed [CM503015]: Call(237): Attempt to reach [sip:[email protected]:5060;user=phone] failed. Reason: Reason Unknown
16:34:35.811 CallLeg:nFailure [CM503003]: Call(237): Call to sip:[email protected]:5060 has failed; Cause: 400 Bad Request; from IP:204.9.202.101:5060
16:34:34.373 CallCtrl:nSelectRouteReq [CM503004]: Call(237): Calling: VoIPline:0078123200031@(Ln.10009@MondoTalk)@[Dev:sip:[email protected]:5060]
16:34:34.358 CallCtrl:nSelectRouteReq [CM503010]: Making route(s) to [sip:[email protected]:5060;user=phone]
16:34:34.342 CallCtrl:nIncomingCall [CM503001]: Call(237): Incoming call from Fax.888 to [sip:[email protected]:5060;user=phone]
16:33:42.968 FaxCfg::updateContact [CM504008]: Fax Service: registered as sip:[email protected]:5060 with contact sip:[email protected]:5100;user=phone