asterisk users - Aug 2020 - One way audio on outgoing calls

    I am having a strange problem with a new provider.  We already have 
a couple SIP trunks working fine.  We are trying a new provider but we 
are having one way audio problems with outgoing calls.  Incoming calls 
do have two way audio, only outgoing calls have this problem.  I do not 
see anything odd with a packet capture and using PJSIP history to 
check.  The provider says that on outgoing calls the get random 
characters instead of the media port for RTP.

     We are using Asterisk 16.12.0 with PJSIP.  The server is behind NAT 
so we have external_media_address and external_signaling_address set to 
the public IP and all relevant ports are forwarded to the Asterisk 
server.  The other SIP trunks work fine, only this new provider has a 
problem and only for outgoing calls.

     An rtp set debug on shows only outgoing packets to the media 
address but no incoming packets.  Why would there be a difference that 
makes it work on incoming calls but not on outgoing?

-- 
Telecomunicaciones Abiertas de México S.A. de C.V.
Carlos Chávez
+52 (55)8116-9161

Hi Carlos

Le 07/08/2020 à 06:33, Carlos Chavez a écrit :
>     I am having a strange problem with a new provider.  We already 
> have a couple SIP trunks working fine.  We are trying a new provider 
> but we are having one way audio problems with outgoing calls. Incoming 
> calls do have two way audio, only outgoing calls have this problem.  I 
> do not see anything odd with a packet capture and using PJSIP history 
> to check.  The provider says that on outgoing calls the get random 
> characters instead of the media port for RTP.
>
>     We are using Asterisk 16.12.0 with PJSIP.  The server is behind 
> NAT so we have external_media_address and external_signaling_address 
> set to the public IP and all relevant ports are forwarded to the 
> Asterisk server.  The other SIP trunks work fine, only this new 
> provider has a problem and only for outgoing calls.
>
>     An rtp set debug on shows only outgoing packets to the media 
> address but no incoming packets.  Why would there be a difference that 
> makes it work on incoming calls but not on outgoing?
We faced this problem and it was a firewall issue on our side. But if 
you say that your provider doesn't get the RTP, I understand that they 
can't return anything. RTP ports ?

Cheers

-- 
Daniel