Hi - I have been experimenting 3CX using a fresh install (version 8) and the 3CX softphone on two separate computers and an iPhone w/ a sip client. I have been unable to get any audio (caller cannot hear callie and callie cannot hear caller) unless I check the "PBX Delivers Audio" option in the capabilities on the extention config screen (Ext | Edit | Other tab). Is this normal? It seems like the softphones should be able to handle the audio directly between them and not through the server. 3CX softphones and iPhone SIP register OK with the server and ring the other extension OK. When the call is answered, there is only silence - not even one way audio. I have done all testing on the LAN (same subnet, no vlans, routers, etc). No host firewalls on the server or either softphone client If a call is sent to voicemail, the system prompts are heard fine, voice message delivers OK. Below is the log snippet from setup and tear down. Again, I do not see anything out of place. Is there additional logging that can be turned on at the 3CXsoftphone? Code: 17:49:38.968 [CM503008]: Call(22): Call is terminated 17:49:31.671 [CM504001]: Ext.12: new contact is registered. Contact(s): [sip:12@XXX.XXX.XXX.54:5060/12,sip:12@XXX.XXX.XXX.17:1850;rinstance=67155cfc8c3f2cfe/12] 17:49:23.812 Session 372 of leg C:22.1 is confirmed 17:49:23.625 [CM503007]: Call(22): Device joined: sip:14@XXX.XXX.XXX.29:4043;rinstance=92b1fbaae80cad4c 17:49:23.609 [CM503007]: Call(22): Device joined: sip:12@XXX.XXX.XXX.17:1850;rinstance=67155cfc8c3f2cfe 17:49:23.609 [MS210007] C:22.1:Answer provided. Connection(by pass mode): XXX.XXX.XXX.29:40018(40019) 17:49:23.609 [MS210001] C:22.2:Answer received. RTP connection[unsecure]: XXX.XXX.XXX.29:40018(40019) 17:49:23.609 Remote SDP is set for legC:22.2 17:49:20.296 [CM505001]: Ext.14: Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [3CXPhone 4.0.11015.0] PBX contact: [sip:14@XXX.XXX.XXX.84:5060] 17:49:20.281 [CM503002]: Call(22): Alerting sip:14@XXX.XXX.XXX.29:4043;rinstance=92b1fbaae80cad4c 17:49:20.156 [CM503025]: Call(22): Calling Ext:Ext.14@[Dev:sip:14@XXX.XXX.XXX.29:4043;rinstance=92b1fbaae80cad4c] 17:49:20.156 [MS210006] C:22.2:Offer provided. Connection(by pass mode): XXX.XXX.XXX.17:40000(40001) 17:49:20.093 [CM503004]: Call(22): Route 1: Ext:Ext.14@[Dev:sip:14@XXX.XXX.XXX.29:4043;rinstance=92b1fbaae80cad4c] 17:49:20.093 [CM503010]: Making route(s) to <sip:14@XXX.XXX.XXX.84:5060> 17:49:20.093 [MS210000] C:22.1:Offer received. RTP connection: XXX.XXX.XXX.17:40000(40001) 17:49:20.093 Remote SDP is set for legC:22.1 17:49:20.093 [CM505001]: Ext.12: Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [3CXPhone 4.0.10858.0] PBX contact: [sip:12@XXX.XXX.XXX.84:5060] 17:49:20.093 [CM503001]: Call(22): Incoming call from Ext.12 to <sip:14@XXX.XXX.XXX.84:5060> 17:49:20.078 [CM500002]: Info on incoming INVITE: INVITE sip:14@XXX.XXX.XXX.84:5060 SIP/2.0 Via: SIP/2.0/UDP XXX.XXX.XXX.17:1850;branch=z9hG4bK-d8754z-5648824d0d5b7d71-1---d8754z-;rport=1850 Max-Forwards: 70 Contact: <sip:12@XXX.XXX.XXX.17:1850;rinstance=67155cfc8c3f2cfe> To: <sip:14@XXX.XXX.XXX.84:5060> From: <sip:12@XXX.XXX.XXX.84:5060>;tag=783fbf4b Call-ID: NjMyODUxNmUwYzNiOWYzMjk1ZjAwZjE2MzcxZjJiMTk. CSeq: 2 INVITE Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REGISTER, SUBSCRIBE, NOTIFY, REFER, INFO Proxy-Authorization: Digest username="12",realm="3CXPhoneSystem",nonce="414d535c01ed5d0f35:2b95f9f66b4872cd1404639c9071d592",uri="sip:14@XXX.XXX.XXX.84:5060",response="5d1c33517cbeac9ef1b77f29780379b7",algorithm=MD5 Supported: replaces User-Agent: 3CXPhone 4.0.10858.0 Content-Length: 0 p.s. I have been having fun with 3CX, looks like a good product so far.