What's interesting is it's a 2500 sending the tones over an analog AT&T line over to a cell phone on AT&T mobile. So I imagine the conversion to a DTMF RTP packet is done by AT&T when it hits the first A-D converter, and travels through the network as that.
What's not clear is if AT&T is picking the DTMF packet off for itself so that the phone never sees it, or if the phone is getting the packet but not converting it back into a tone.
I've opened a thread with AT&T support here:
https://forums.att.com/conversation...637a8?commentId=62b4c0224333500318b7f991..waiting to see if that yields a solution.
