Hello, I’ve done quite a few google searches, but can’t find a resolution to my issue, which is:
- When I dial a number straight from MicroSIP through my PBX, DTMF works just fine
- When I use a “merge” context in to a conference, DTMF does not pass
I have tried all DTMF options (Auto, inband, sip-info, RFC2833), and I’ve matched it to my trunk, but when an inbound call to the conference is received, DTMF does not pass.
use case: I call “scammer” numbers and my calls are often sent to voicemail. My DID is logged and they robo-dial me back. The call-back puts them in a conference (inbound route sends to the conference) which other friends (scam-baiters) are dialed in to. When the IVR inbound says “press 1 to speak to a scamazon agent”, we can press 1 all day long, but the IVR doesn’t detect it.
Why would DTMF responses work when the call is sent to an extension (MicroSIP auto-answer), but DTMF isn’t passed in the conference?