IAX2 remote extension has bad audio


I have a remote extension and the audio is a little crackly and occasionally has dead spots for a second or so at a time, I was originally using a sip but it was failing to register some times but now I have an IAX2 extension it has no issue with registering but the audio is a little bad.

There is only one remote user at the moment.

The bandwidth shouldn’t be an an issue (down: 18298 Kbps up: 1537 Kbps) and the remote user is on a fiber connection0 using Zoiper.

Any ideas that would be grate.

That’s always a network issue, bandwidth is not the limiting factor, it is all about latency, either sip or iax2, many carriers delay (or perhaps I should say FW :wink: ) voip connections on SIP and IAX2.

Thanks, I had a server die on me due to an update, and I had no audio issue there, but since I have done a new install the audio has never been the same

Sorry can’t help you there, way too little info or diagnostics given.

Sorry, can you point me in the right direction to gaether the information?

I did this test

nmap -p 4569 xxx.xx.170

Starting Nmap 5.51 ( http://nmap.org ) at 2014-12-05 16:36 AEDT
Nmap scan report for xxx.xx.170
Host is up (0.19s latency).
4569/tcp filtered unknown

Nmap done: 1 IP address (1 host up) scanned in 2.79 seconds


I have no experience with connections in the Philippines but IAX2 runs on UDP not TCP so

nmap -sU -p 4569 xxx.xx.170

and the best you can get is from the Asterisk CLI:

iax2 set debug on

from bash

tcpdump -vv -n udp port 4569

would give you more information, look carefully at the timestamps and interleaving of packets