davidav Posted October 19, 2010 Report Share Posted October 19, 2010 We are suffering a lot of pain with outbound calls dropping out - happens pretty regularly but not with every call - probably about 30-50% of outbound calls. I have no real idea why this is happening - we have tried all sorts of things to improve but generally 1 step forward, 1 or 2 steps back. Looking at a trace for a dropped call today (a normal VOIP call to a PSTN landline), there are two things that look suspicious: 1. We always seem to get the following "falling back to transcoding" messages when the call is initiated:  2010/10/19 14:55:58: Set packet length to 20  2010/10/19 14:55:58: Sending RTP for 4f3c17cb@pbx#1193819909 to 126.96.36.199:59256  2010/10/19 14:55:58: 4f3c17cb@pbx#1193819909: RTP pass-through mode  2010/10/19 14:55:58: email@example.com#510adaefc6: RTP pass-through mode  2010/10/19 14:55:58: Cannot pass through on firstname.lastname@example.org#510adaefc6, falling back to transcoding  2010/10/19 14:55:58: Cannot pass through on 4f3c17cb@pbx#1193819909, falling back to transcoding  2010/10/19 14:56:40: SIP Rx udp:10.0.1.21:5060: 2. Just before the call dropped out, there is the following mysterious entry in the log. Why is it trying to connect to 188.8.131.52?? A quick whois search suggests this is something to do with commcast.  2010/10/19 14:57:00: Last message repeated 7 times  2010/10/19 14:57:00: Could not connect to 184.108.40.206:443  2010/10/19 14:57:00: Could not send via TCP: 0 bytes  2010/10/19 14:57:03: SIP Tr udp:220.127.116.11:5060: Any ideas on either of these issues? Quote Link to comment Share on other sites More sharing options...
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