DTMF being passed both ways

When using Asterisk to dial into a SIP provider, leaving dtmfmode as rfc2833 for that SIP ‘friend’ enables DTMF to be recognized by the SIP provider. Using a Dial(SIP/XX|10|t) should enable transfers on the SIP provider’s side, but Asterisk does not recognize the DTMF thats required to initiate transfers when using dtmfmode=rfc2833.

When I switch to inband in sip.conf, Asterisk now recognizes the DTMF and initiates the transfer but the DTMF no longer get passed to the SIP provider.

I have tried INFo and AUTO dtmfmode, and have not had luck getting DTMFs to be recognized both ways.

Is there a way to pass DTMFs through Asterisk from the callee and called side?

this is an issue with your SIP provider. They are not encoding the DTMF being passed inward, so neither setting gets both sides of it.

I think your best bet might be to separate the sip.conf entry into an incoming and outgoing section.


register => user:pass@provider_in

blah blah blah same stuff you had before

copy of above