If the AA receives no tones, after three retries it should connect to the "no input" number, by default the Phone port. Upon answering that, if there is no audio, the problem is obviously unrelated to DTMF. If audio is ok, you can try pressing buttons at the calling end and listening for DTMF on the phone.
@Stewart: the issue is that DTMF is not recognized. that is the first part of issue.
Why do you care about the GV path, since you already have the OBiTALK path working fine?
@Stewart: we have seen that Obitalk voice network may not be very reliable with many unscheduled downtimes. GoogleChat that way is more reliable.also, SIP is blocked in the country where Obi is deployed
I know little about Jingle, but why do you care about the relay? Latency? Privacy? Because of subtle issues associated with NAT port translation, a relay approach is usually more reliable and robust. It also enables the provider to transcode, monitor quality, etc. For example, Vonage and Callcentric always proxy the media. Low cost providers often don't, mostly to economize on their bandwidth requirements.
@Stewart: latency/privacy is the main reason.
i wonder if anyone has tried calling obi-obi via GoogleChat (in the format: **1<targetobigoogleuser>)