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<p class=MsoNormal>Hello,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span lang=EN-US>I’m having trouble with this
configuration with sangoma A400 card.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>What happens is this : the call is
established (bridged from FXS to FXO) to an IVR, then the caller press some key.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>At that moment, the sangoma card detects
the DTMF on the FXS channel, and queue the DTMF to be sent of the FXO channel.
As a result, to the remote IVR, the DTMF is received twice (once inband, and a
second time when generated from the FXO).<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I sometimes get an even worse scenario
where the DTMF is detected by the card on both channels, and an endless loop start
as the DTMF gets detected by the other channel when generated and so on and so
forth.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I tried to stop DTMF generation by adding
the following lines to the dialplan before the bridge<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><action
application="stop_dtmf" data=""/><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><action
application="stop_dtmf_generate" data=""/><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><action application="bridge"
data="openzap/2/2/$1"/><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>But this did not help.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I could kindof solve the endless loop by
modifying zap_io.c in zap_channel_set_state, when the new state is dialing
(which means the FXO channel is an outbound one, and I therefore don’t
need DTMF detection) I do a zap_clear_flag(zchan, ZAP_CHANNEL_DTMF_DETECT);
which prevent further DTMF detection on that channel.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I don’t know where to carry on now,
as just preventing DTMF generation on outbound FXO channel would prevent DTMF
generation where A leg is sofia or any other.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>François<o:p></o:p></span></p>
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