Topic: One Way Audio but only on AA answered calls. Router guys - help?

[matherton]

First post, figured i'd start the topic off with an interesting trouble. 

Zultys MX30 on V7.0.7 s/w, sonicwall router with 2 different internet connections - 1 for Voice and 1 for Data (plus the obvious fail-over for data), ThinkTel ITSP, SIP trunks with DID's.

Interesting new problem that just cropped up, out going calls are fine.  Incoming calls that ring the DID numbers that go directly to a physical set are fine, 2 way audio on every incoming call.  If the Auto Attendant answers, most of the calls are answered with dead air.  Callers can not hear the auto attendant, if they know what to press, they can still transfer through to an extension - but again, only 1 way audio. 
If I change the destination of the DID (that is answered by the AA) to a set - every call that is answered by that set has 2 way audio.  I tried more than 60 calls to test this. 

ANY DID that is answered by the AA has a great possibility of 1 way audio.

ThinkTel (ITSP) has been absolutely awesome with their tech support.  Zultys has been 'ok'.  ThinkTel has done wireshark tests at their end (while i'm doing them at my end), and have found that the customer's sonicwall router was intermittantly sending voice UDP packets out over the data side of the network despite it being programmed to do otherwise. 

The customer - feeling very non-plussed that their 'excellent router' might be to blame, unplugged the 'data' internet network connection cable from the sonicwall and tried again with incoming calls - it still failed with one way voice, which they say "proves its not our perfect router". 

So my question is this: Even if the second internet connection (that is programmed only for "data") is unplugged from the sonicwall router, is it possible the router is still trying to send packets to that physical port? 

I find it very difficult to troubleshoot when the vendor says "our equipment is perfect, its not our equipment, our wireshark proves it", the ITSP says "its not our service, the wireshark proves it", the router vendor says "the router is programmed, its not our problem".  2 days so far I have spent on this problem. 

The 70 year old phone man we have working with us shakes his head, "tip and ring baby". 

[Marc Haycook]

If traffic is still going through the Sonicwall, it does no good to just unplug the second Internet connection. The only way to prove it is or is not the Sonicwall is to take it completely out of the network.

[matherton]

Confirmed what you say Marc.  Removed the Sonicwall and connected directly to internet with a Cisco Linksys 2500 (sold at Staples Business Depot for 65$), minimal programming just 5060 and the audio ports forwarded, and it worked.  I made 60 calls into the system, 100% pass.  Customer was NOT happy and spent the day on the phone with Sonicwall TS...  Didnt need a wireshark to prove that.

[NFCphoneman]

Good job!  Just shows you don't always need the fancy tools to prove what your gut is telling you.  Keep the $65 router in your truck for future use!

[matherton]

*sigh* customer doesnt believe that the router is the issue.  Even after watching 60 calls happen without incident.  they believe somehow the Zultys box is mis-marking some intermittant packets and the sonicwall is "only doing its job" at "correctly" routing the packets as it was programmed to do.  I find it difficult to continue to be supportive when they are so focused on something they have nailed such deep belief in a product.  They continue to operate using the sonicwall and continue doing wireshark tests and send me odd results. 

dont make me bring the 60$ router over and spank the sonicwall again.

[KLD]

You can only be dealing with CGs, no one else is that stupid.

[ttech]

Have you turned off Alg in the router? I think sonic wall calls it something different though.

[matherton]

I asked him about ALG, he says it is, and I dont know anything about that router type.  They are STILL limping along with this, doing wireshark after wireshark, I have to admire their tenacity, and I hope they (and sonicwall) get it figured out.