For an off-net ad-hoc conference to work ( the initiator uses a Cisco IP phone, the rest are PSTN callers) is a hardware conference bridge a must? We have only a software conference bridge, it's not working.
voice class codec 1
codec preference 1 g711ulaw
codec preference 2 g711alaw
codec preference 3 g729r8
dial-peer voice 10 voip
voice-class codec 1
session target ipv4:220.127.116.11
Sorry, codec selection is only available for VoIP dial-peers
you can create another dial-peer with
incoming called-number .
instead of destination-pattern
and set the voice class codec in it to match it as the incoming dial-peer
Here you have some additional info:
A busy tone is received when the user calls across a gateway over a dial peer with a default codec
voice class codec