Asterisk problem in Vietnam

Hi all

I have setup the asterisk server in HCM. The asterisk connects to analog PSTN line by using the digium TDM2400P card.

It cannot dialout and calling. When I call in to asterisk, the phone(asterisk side) rings. Then the phone(asterisk side) is answered. The caller (PSTN side) still rings. It does not know that the destination has already answer. And the phone(asterisk side) will here the strange signal, it sounds like the pulse.

When I dialout, the asterisk can bridge the call but the destination does not ring and the phone (asterisk side) has got the same strange signal as the above.

I have tried to change all singnaling in zapata.conf and zaptel.conf but It does not work.

I think the signaling at Vietnam is not the standard because when they dialout from normal analog phone, they will here the pulse signal before it rings the destination. I have experienced to setup asterisk in Thailand. There is no problem.

Does anyone has experience with setting up asterisk in vietnam?
Please advice me.

Thanks,
Thawat

And the phone(asterisk side) will here the strange signal, it sounds like the pulse.

What loadzone and defaultzone do you mention in zaptel.conf?
This will affect the tone settings.

Have to tried DTMF signalling?