ConfBridge, the sound of silence

First of all, thank you for share and help in this wonderful forum.

I would need to implement this behaviour:

  • an external user calls 0656566999 from the PSTN; he enters the conference room
  • four SIP phones ring all at the same time
  • when answered, the SIP call is automatically redirected to the conference room

With my dialplan I basically get what I need, but the external user hear no sound until EVERY sip call is answered (or timeouts). In fact, the sip phones ring SEQUENTIALLY. Is there a way to get all call legs automatically connected to the conference room? Even if the room is empty, music on hold is played (music_on_hold_when_empty set to yes in confbridge.conf)

Here’s the dialplan snippet:

[b]exten => 0656566999,1,Answer()
same => n,Originate(local/201@incoming,exten,confroom,100,1)
same => n,Originate(local/202@incoming,exten,confroom,100,1)
same => n,Originate(local/203@incoming,exten,confroom,100,1)
same => n,Originate(local/204@incoming,exten,confroom,100,1)
same => n,ChannelRedirect(${CHANNEL},confroom,100,1)

exten => 100,1,Answer()
exten => 100,n,ConfBridge(100)[/b]

Any help appreciated!