Asterisk Out of Band DTMF Mode

Hi all,

I use asterisk 13.8 with PJSIP. I have SIP trunk beetwen my provider.
My issuse is my provider said me “you have to use out of band dtmf method” also I set the dtmf_mode=rfc4733 and he said me "this mode is not seem out of band, it is inband dtmf method please chek your PBX."
How can I check inband or out of band

Thanks for your replay

That mode is most certainly out of band from the audio. It’s sent using different RTP packets which convey the digit. You can confirm it is set by doing "pjsip show endpoint " on the CLI. You may want to get clarification on what “out of band” means in their eyes.

They may mean INFO where the DTMF is sent on the signalling path, but this is considered obsolete.

Or it could be a language problem, and they really mean inband!