An inbound call is received from a SIP trunk. The call is answered and then parked using the park softkey. When trying to pick up the call on another extension a fast busy tone is heard. The call cannot be retreived and is stuck until the calling party hangs up.
This only happens with received calls from the SIP trunk. Parking and picking up outbound calls made via the SIP trunk works fine. As do internal calls and calls via ye olde voice card.
It appears from the debug attached that there is a disconnect cause 28 (invalid address). It also seems that when the park softkey is pressed the system sends a REFER message to the sip provider which I expect shouldn't be happening as the CME system should manage the park internally.
I'm far from an expert and I've battled with this one for some time so I'd very much appreciate someone helping me to join the dots. Thanks.
Notes
-The SIP trunk requires modification of the SIP headers due to the provider Sipgate using non numeric characters in the user id).
-For the debug the call was answered on extension 301, parked on 501 and attempted to be picked up on extension 111.
-Transcoding seems to be working fine so I don't think this is a codec issue.
