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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>In some configuration experiments, I have one IAX softphone
connecting over the internet to my Asterisk system. (I should note that,
while there IS a NAT firewall between Asterisk and the public Internet, I have
port forwarding set up on that firewall to send all IAX traffic to the Asterisk
machine.)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The IAX softphone connects to either an analog phone on an
FXS port on the Asterisk server, or a SIP phone on its local network.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>When I make or receive calls from this IAX softphone,
everything works fine. However, if one side of the conversation initiates
a hold for more than a couple seconds, the synchronization gets all off. When
the hold is ended, there is up to sometimes 30 seconds or more of latency.
Sometimes it’s shorter – 5 to 15 seconds, and those seem to “catch-up”
after a few minutes. This also happens with transfers, which don’t
carry the music-on-hold. With real short hold times (a second or two),
the sudden synchronization problem is much less pronounced – a second or
two perhaps. The longer delays don’t seem to ever catch up –
or at least not within a couple minutes, beyond which, I haven’t tested.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>This occurs with or without the jitter buffer.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Has anyone else experienced this? And if so, I would
appreciate if someone could point me in the right direction to make this issue
go away.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m fine with the normal latency caused by the internet
link, but right now, hold is completely unusable.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks in advance.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>- Robert<o:p></o:p></span></font></p>
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