No audio on some outbound calls

[willieven]

I am really getting frustrated with this issue,

The firewall checker says everything is working yet i still get no audio on some calls.

Here is the log: http://pastebin.com/08NvWKPB

Any help would be awesome.

 

[lneblett]

I saw several STUN failures in the logs. If you have a fixed public IP, try setting the IP as the specified address and turn STUN off.

You really need to run wireshark and capture the data. Presumably RTP data was sent, it is merely a question of where? The 3CX logger will only show what it sees relative to its IP and if the data inadvertently got sent to some other IP, it will not show where it was sent, only that it expected to see it and did not. This will sometimes happen if the 3CX instance has 2 NIC cards installed.

 

[willieven]

We don't have a static ip. I'm going to download wireshark and see if i pick anything up.

Is it better to use random public stun server than the default ones?

 

[lneblett]

With regard to STUN, not necessarily. I only noticed that some STUN requests had failed and that some ports also failed and possibly this may be related to the issue. A fixed IP simply eliminates one of the variables and makes the odds of having a successful experience much better.

A moving IP tends to make it all a moving target, but getting a DDNS associated may also help in some instances, most notably so with the SIP provider. DSL installs seem (to me at least) to have a far greater to move the IP around, so I try and avoid them.

When you get wireshark running, capture one call at a time. When you get a call that exhibits the problem, stop the capture and then go to the tab labeled as "telephony" select the two sides of the call and then hit flow. This will give a graphical representation of the data flow between IP engaged in the call. You should see the SIP provider's, your 3CX instance IP and the phone IP itself. Hopefully, you will see a 4th or unrecognized IP some other indication of what is happening.

You might also try PBX provides audio in the settings if not already set.

 

[willieven]

It happens on every second call, wireshark is a bit confusing but what i did see is "destination port is unreachable" and "Header checksum: 0x0000 [incorrect, should be 0x6996 (may be caused by "IP checksum offload"?)]"

Dont know if that means anything?

 

[lneblett]

Define the exact scenario by which this occurs. Who dials, what are we dialing (remote extension or a true telephone number), using SIP or PSTN (via gateway), what is heard and not heard (but expected) by each side. Is it just one number or any number as long as it the second call?

Be as explicit as possible going step-by step.

Is the PBX providing audio?

 

[willieven]

Ok here we go.

3 x Yealink T20's
3cx free edition running on windows 7
Belkin router.
No gateway, just SIP

The 3cx server is placed outside the NAT, also all ports are forwarded but this router can only forward 20 ports so i have changed the ports used to 9000 til 9015(not sure if this might be causing it?).

All internal calls work fine, its just on outbound calls where a physical number is dialed.
This happens to every second call, we get a the ring tone then when the person answers i cant here them and they cant hear me. If the same number is redialed the audio works fine. This is on every number and "true telephone numbers". Internal extensions work fine.

This happens from any extension and not just mine.

The pbx is providing audio.

 

[lneblett]

If you can only forward 9000-9015, did you also change the settings within 3CX to correlate to same?

 

[willieven]

if you mean, "ports to use for external leg of VoIP provider calls" yes i did

 

[lneblett]

OK, good as the range is more than enough for 2 calls.

Did you disable any SIP ALG settings in the routers? If not do this as well.

 

[willieven]

The router does not have any SIP ALG settings, this is a normal dsl router.

 

[lneblett]

Below is your earlier post. I have underlined the areas of concern. The issues seemingly point to the firewall as you do not have a reliable connection or ability to consistently port forward. Not having seen the wireshark capture of the issue, I can't do more other than to suggest you try a different make of router. Getting a fixed IP would also help matters, but I know that this may not be possible depending upon carrier. In my area, you can only get a fixed IP when you subscribe to their highest offering. Unfortunately, most folks don't reside that close to the CO and as a result have to settle for the highest available in that area, which then precludes their being able to get a fixed IP -

14-Jan-2013 10:20:43.427 [MS105000] C:12.2: No RTP packets were received:remoteAddr=196.28.95.12:10708,extAddr=0.0.0.0:0,localAddr=192.168.1.10:9010
14-Jan-2013 10:20:42.532 Leg L:12.2[Line:10000>>0828088960] is terminated: Cause: BYE from PBX
14-Jan-2013 10:20:42.532 [CM503008]: Call(C:12): Call is terminated
14-Jan-2013 10:20:42.531 Leg L:12.1[Extn] is terminated: Cause: BYE from 192.168.1.3:5062
14-Jan-2013 10:20:25.577 Currently active calls - 1: [12]
14-Jan-2013 10:20:23.802 [CM503007]: Call(C:12): Line:10000>>0828088960 has joined, contact <sip:[email protected]:5060>
14-Jan-2013 10:20:23.802 [CM503007]: Call(C:12): Extn:10 has joined, contact <sip:[email protected]:5062>
14-Jan-2013 10:20:23.801 L:12.2[Line:10000>>0828088960] has joined to L:12.1[Extn]
14-Jan-2013 10:20:23.801 [CM505003]: Provider:[Generic VoIP Provider -] Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [MWEB Session Router] PBX contact: [sip:[email protected]:5060]
14-Jan-2013 10:20:23.353 Provisional response (malformed) arrived to Leg L:12.2[Line:10000>>0828088960]
14-Jan-2013 10:19:58.114 Provisional response (malformed) arrived to Leg L:12.2[Line:10000>>0828088960]
14-Jan-2013 10:19:55.572 Provisional response (malformed) arrived to Leg L:12.2[Line:10000>>0828088960]
14-Jan-2013 10:19:54.692 [CM503025]: Call(C:12): Calling T:Line:10000>>0828088960@[Dev:sip:[email protected]:5060] for L:12.1[Extn]
14-Jan-2013 10:19:54.690 [MS101003] C:12.2: Possible firewall problem. Address mapping failed on STUN server 199.192.206.228:3478 for local address ":9010"14-Jan-2013 10:19:54.690 [MS201000] Use STUN server 'stun.3cx.com:3478'
14-Jan-2013 10:19:54.690 [MS101005] STUN request failed for ports 9010,9011 on STUN server 'stun3.3cx.com:3478'
14-Jan-2013 10:19:53.575 Currently active calls - 1: [12]14-Jan-2013 10:19:51.667 [MS201000] Use STUN server 'stun3.3cx.com:3478'
14-Jan-2013 10:19:51.667 [MS101005] STUN request failed for ports 9010,9011 on STUN server 'stun2.3cx.com:3478'

 

[nictwo2269]

Could you possibly put the 3CX machine in DMZ mode and see if that corrects the issue as a temporary fix? I can see the only 20 port factor being an issue.