Why? There is nothing, so far, that has been presented that would require the PBX to be rebooted. So why issue a reboot when it’s not really needed?
Is the PBX remote to all the agents and the phones? When a call is Transferred (be it the standard transfer or the in-call feature codes) the first thing that happens is the other party is immediately put on hold. That’s very important to understand because when a HOLD is initialized this sends a new INVITE to the system with updated SDP/media details. It tells the call that either 1) Send incoming audio from the other party to a blackhole (0.0.0.0) or 2) It changes the media stream to be “Send Only” meaning it won’t receive incoming media from the other side. Now when you take a call off HOLD, the process is repeated but this time the INVITE changes the SDP/media back to be a two way communication.
So it is sounding like something is happening when the agent is taking the customer off hold and the SDP/media isn’t being handled right. What we need here is an actual SIP trace of a call being put on hold and taken off hold that this happens to.
Just do the following:
sip set debug on (if using CHAN_SIP)
pjsip set logger on (if using Chan_PJSIP)
Make call, put on hold, take off hold, have 1 way audio issues, hang up call. Copy and paste the ENTIRE debug from the initial INVITE to the last message and post it so it can be looked at.