Finally managed to get a reproducible failure on this, but don't understand SIP enough to know where it's going wrong. I have two local numbers that I can call via my local telco over a SIP trunk (MetaSwitch) - one reliably demonstrates the behavior, the other reliably works normal: The call that is working normally (leg w/ provider): INVITE w/ neither sendonly nor sendrecv 100 Trying 183 Progress w/ a=sendrecv 200 OK w/ a=sendrecv The call that is going into on-hold immediately (leg w/ provider): INVITE w/ neither sendonly nor sendrecv 100 Trying 180 Ringing 200 OK w/ a=sendonly INVITE w/ a=sendrecv 100 Trying 200 OK w/ neither sendonly nor sendrecv Call that goes into on hold immediately (leg w/ device): INVITE w/ neither, but has sdp 407 INVITE w/ neither, but has sdp 100 183 w/ neither 200 w/ neither UPDATE w/ sendonly (which is after the second 200 OK above) 200 OK w/ recvonly I'm going to try and do some more digging on this tomorrow, but if someone has any insights here on what the proper/expected behavior is, I sure would love to hear it. It seems like this may be somewhat related to FS-9765 - however there is no invite w/o an SDP. Also similar sounding to FS-11234. I'm happy to take this forward to provider (I'm inquiring with them as well) but would be helpful to have some more details on which piece is behaving incorrectly. -- Nathan -------- Original Message -------- From: Nathan Neulinger Sent: Tue, Sep 4, 2018 2:45 PM CDT To: FreeSWITCH Users Help <freeswitch-users@lists.freeswitch.org> Subject: Phone spontaneously going into Hold when a call is established? I had seen this symptom a few times randomly, and just got a couple of reports from users where a call to an outside number was going immediately to 'On Hold' when the person answered. Is there anything in the SIP/RTP stream that could be expected to trigger that sort of behavior? I've seen it from a polycom, and I believe one of the user reports today was with a yealink. User report was with a recently upgraded 1.6 -> 1.8 deployment. I believe the previous times I've seen it would have been on git builds of 1.8, but not certain. -- Nathan ------------------------------------------------------------ Nathan Neulingernneul@mst.edu Missouri S&T Information Technology (573) 612-1412 System Administrator - Architect -- ------------------------------------------------------------ Nathan Neulinger nneul@mst.edu Missouri S&T Information Technology (573) 612-1412 System Administrator - Architect