Hi Bote, Extension B sends a REFER event to FS that responds with a 202 Accepted and after a NOTIFY. I guess it is the same as using dialplan with att_xfer. Alex. ________________________________ De: freeswitch-users-bounces@lists.freeswitch.org <freeswitch-users-bounces@lists.freeswitch.org> em nome de Bote Man <bote_radio@botecomm.com> Enviado: terça-feira, 29 de março de 2016 15:04 Para: 'FreeSWITCH Users Help' Assunto: Re: [Freeswitch-users] Attended Transfer with one-way audio What does the Flash key do in SIP? Bote From: Alex Pierry Sent: Tuesday, 29 March, 2016 08:25 To: freeswitch-users@lists.freeswitch.org Subject: [Freeswitch-users] Attended Transfer with one-way audio Hi All, I'm facing a strange behaviour in FS after a Attended Transfer. For the A leg listen the C leg, C needs to press some DTMF key. Otherwise only C leg can listen A leg. ... An important point is that all transfers are made pressing "Flash" key in SIP Phone not by att_xfer in Dialplan. So, any clue to start? Thank you, Alex.