Solved No ringtone for outgoing external calls

[JerN]

When I dial an external number using either the SIP phone (Yealink T46S) or the 3CX softphone I can not hear it ringing, there is just silence. It does however ring at the other end and if the call is picked up the audio works just fine. When I call between extensions I can hear the ringtone so that I know that it has established the connection.

The firewall checker shows everything green. I'm not sure what could cause this.

 

[JasonNadeau]

... what kind of connection to the outside world are you using ? Sip trunks ? PRI ? Analog lines ?

 

[JerN]

I'm using SIP trunks. I was getting the audio until today.

 

[JasonNadeau]

was this all of a sudden with ZERO changes in 3cx ??
... if so, I'd check with the sip trunk provider. Otherwise I'd consider rebooting the router and would check the supports reinvite / replaces in the sip trunk.

 

[JerN]

I didn't make any change in 3CX. I noticed it some time after updating the 911 contact information with my SIP provider. I did contact the provider and got the following response:

"That's a setting on 3CX.
I believe it's called “Inband Progress Tones Generation”.
Check with your 3CX vendor or pbx admin on how to update the setting.

Sorry not something we can do trunkside."​

I've rebooted everything at my end and no change.

 

[leejor]

If you call a number that is busy, what do you get?

You need to determine (using Wireshark) if the provider is sending a 180 Ringing message. If they are, then you should be hearing Ring back. If the are not, and just sending a 200 OK, when the call is answered, then you'd have to have a chat with them about that

 

[JerN]

I'm just coming back to update the solution to this issue. The SonicWALL IPS was blocking the 180 Ringing message. To resolve this either turn off blocking of Low Priority Attacks or to just disable the one rule turn off the IPS Policy for INFO: SIP Session Progress (Signature ID: 1188)

 

[YiannisH_3CX]

Glad to hear the issue is resolved and thank you for sharing your solution