Weird one way audio issue

Asterisk Asterisk Support
1

I have been having a pretty weird one-way audio issue that I can’t seem to figure out. I have my Asterisk box installed on CentOS. I’m running Asterisk 1.4.24.1 with FreePBX 2.7. I am using MagicJack as a SIP trunk for inbound and outbound calls. Well, my weird issue is this.

If I have my inbound route to go directly to one of my internal extensions I can hear the audio just fine on both sides.
If I dial out from an internal extension, the external phone can hear me fine, but I can’t hear them.
If I have my inbound route be my IVR, the external phone will choose an option and then my phone will ring and they can hear me but I can’t hear them.
If I call an internal extension from an internal extension, audio is fine on both sides.

My asterisk box is up in the cloud and it’s not behind NAT or a firewall(disabled to help problem solve). My internal phones are on my home network which is behind a pfSense firewall/router. I have allowed all traffic in and out in the firewall for testing. I have not done port forwarding to a phone because I have multiple phones. I have done a Wireshark capture on a one-way audio call and it all appears like traffic is flowing fine both ways. Wireshark shows g711U being used for audio, which is what Magicjack uses by default.

2

Hi

Your SIP options for your extensions should have

nat=yes qualify=yes canreinvite=no
for starters.
However, you have an RTP issue by the sounds of things.
While not knowing everything, here are some questions you should look at:

  • What phones are you using ? Some phones are more NAT friendly than others. Try another brand (if practical). Try Xlite as its free.
  • Have you tried using a public Stun server ??
  • Have you tried a generic router ? PFSense has lots of cool features, but may have something that screws with the SIP / RTP.
  • What happens when you bypass the router and just run one of the phones on a public internet connection ??

Have you tried removing the unused codes and just run ulaw ?

Hope this helps. Let us know how you go.

Cheers
Chris