I am testing making calls with x-lite 4. Although it doesn&#39;t send a ptime in its INVITE/SDP, i can see it is sending RTP using ptime=40 as I can count 25 UDP packets per second.<br>When I try to bridge this to PSTN which responds with PCMU, at the PSTN side I hear trembling/metallic/robotic audio.<br>
<br>I was suggested to set FS to use ptime=40, so I&#39;ve tried setting codecs with speex@8000h@40i<br><br>But it doesn&#39;t work. I get: &quot;488 Not Acceptable Here&quot; (Reason: Q.850;cause=88;text=&quot;INCOMPATIBLE_DESTINATION) <br>
<br>So it seems only ptime=20 is supported as listed here:<br>
<a href="http://wiki.freeswitch.org/wiki/Codecs#Transcodable_codecs" target="_blank">http://wiki.freeswitch.org/wiki/Codecs#Transcodable_codecs</a><br><br>Could mod_speex be changed to work with ptime=40 too?<br>Or is there anything else that i can try?<br>
<br>regards,<br>takeshi<br><br>
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