Incomming call (from dahdi) -> direct to SIP extension -> blind transfer to conference = all ok - external call in conference and SIP extension line released.
Incomming call (from dahdi) -> queue -> SIP extension -> blind transfer to conference = problem - external call in conference but SIP extension not released line.
Screen in attach.
About spy in conference understand.
I have error with blind transfer from user in queues to conference - after transfer incoming call to conference, sip line of user form queues is not released. The line of user remains busy until incoming call not complet.
No sounds in spy mode (listen / whisper) only in conferences. Button listen / whisper work well with other internal numbers. If i call 555 + number conference sounds is good, but it is inconvenient for the user.
All the same, there is no sound. Output for asterisk -rx "core show channels concise" with and without force_parameter_delimiter=','
DAHDI/pseudo-922601214!default!s!1!Rsrvd!(None)!!!!!3!47!!1418758260.206057
DAHDI/i2/889658064166-31d!from-internal!STARTMEETME!4!Up!MeetMe!201,oTMr,!89658064166!!!3!30!!1418758277.206075
DAHDI/pseudo-2103507193!default!s!1!Rsrvd!(None)!!!!!3!47!!1418758260.206059
DAHDI/i2/88162280360-31c!from-internal!STARTMEETME!4!Up!MeetMe!201,oTMr,!88162280360!1418758252.206045!1418758252.206045!3!56!!1418758252.206045
SIP/1002-00000317!from-internal-increase-vol!!1!Up!ChanSpy!CONFERENCE/201,dq!1002!!!3!12!!1418758295.206085
Hello, transfer is now working, but no sound in listen/whisper mode. If cal to 555 (freepbx spy channel) + number extension - all good.
Same problem for me. Asterisk 12.6.1 FreePBX 12.0.13 Ubuntu 14.10 FOP 2.28. Not working transfer (blind and attended) and no sound (and not working mic) in 'listen&whisper' mode for conference (the button listen and 'listen&whisper' are working).