Hello all, I have everything working just fine and have learned a lot about SIP and VoIP over the past few weeks. There is just one aspect of 3CX that I can't seem to get to work: receiving faxes. I have a Fax Server set-up, extension 88. When I call that extension directly from another phone, the fax picks up and immediately disconnects. There is no fax tone to be heard. I don't know if it's supposed to be like this, or that at least a fax tone should play? When I call the extension from outside, using DID, the same happens. The call is answered and dropped immediately. The logs look like this (this is when calling from inside with a phone, same entries appear when calling from the outside with an actual fax device): Code: 22-jan-2016 22:50:54.679 [MS105000] C:2.2: No RTP packets were received:remoteAddr=127.0.0.1:13702,extAddr=0.0.0.0:0,localAddr=127.0.0.1:54620 22-jan-2016 22:50:53.249 Leg L:2.2[Fax] is terminated: Cause: BYE from PBX 22-jan-2016 22:50:53.248 [CM503008]: Call(C:2): Call is terminated 22-jan-2016 22:50:53.246 Leg L:2.1[Extn] is terminated: Cause: BYE from PBX 22-jan-2016 22:50:51.591 [MS205001] C:2.1 RTP: Party address changed from 192.168.1.196:1104 to 82.73.XX.YYY:1104 22-jan-2016 22:50:50.156 [CM503007]: Call(C:2): Fax:88 has joined, contact <sip:firstname.lastname@example.org:13006> 22-jan-2016 22:50:50.153 [CM503007]: Call(C:2): Extn:10 has joined, contact <sip:email@example.com.XX.YYY:5080> 22-jan-2016 22:50:50.151 L:2.2[Fax] has joined to L:2.1[Extn] 22-jan-2016 22:50:50.098 [CM503025]: Call(C:2): Calling T:Fax:88@[Dev:sip:firstname.lastname@example.org:13006;user=phone] for L:2.1[Extn] 22-jan-2016 22:50:50.047 [CM503027]: Call(C:2): From: Extn:10 ("10" <sip:10@FQDN.FQDN.com:5060>) to T:Fax:88@[Dev:sip:email@example.com:13006;user=phone] 22-jan-2016 22:50:50.047 [CM503004]: Call(C:2): Route 1: from L:2.1[Extn] to T:Fax:88@[Dev:sip:firstname.lastname@example.org:13006;user=phone] 22-jan-2016 22:50:50.046 [CM503001]: Call(C:2): Incoming call from Extn:10 to <sip:88@FQDN.FQDN.com:5060> I am using a non-certified SIP Trunk provider, which does support T.38. But since I'm getting the same behaviour when calling internally, I'm not even sure that matters. To me, it seems like the Fax Server is running in a seperate process on the server and should produce the 'fax welcome tone' when joining any SIP call. But it's not making that sound, so the PBX disconnects the call entirely. But I'm not sure if I'm reading this right, if it's supposed to work like this, or something else is up. Any help would be greatly appreciated!