[pjsip] Problem with Toshiba gateway

[Michael Goffioul]

Hi,

I've build a simple SIP application on Android using PJSIP (SVN rev 5435)
and the PJSUA2 API. It has been working fine so far, but we've encountered
a problem when deploying it against a Toshiba gateway (Strata CIX).

When a 3rd party (e.g. external phone) is making a call, our Android device
receives the incoming call and starts ringing. However, the calling party
(the external phone) does not hear any ring tone.

When processing the incoming call, our code is doing the following:

CallOpParam callParam = new CallOpParam();
callParam.setStatusCode(pjsip_status_code.PJSIP_SC_RINGING);
pjsipCall.answer(callParam);

I've made network capture on the Android device, and I can see the statuses
being sent back by the Android device towards the gateway: first there's
status 100, then there's status 180. Not sure where status 100 is coming
from, I suppose it's generated internally by PJSIP.

On the same device, when I'm using the Android SIP stack instead, the
problem does not occur and the calling party hears a ring tone. We also
have another device running Linux and linphone, where the problem does not
occur either.

We usually test our app against Asterisk gateways and the problem does not
occur either.

I'm not really a VoIP expert, I'm just trying to use off-the-shelf
component. Am I missing something obvious? Or is there some setting I need
to use to "tell" the gateway to play the ring tone?

Thanks,
Michael.