One way audio - IncrediblePBX doesn't have this issue

On a Hyper-V on Windows Server 2012 R2, I’ve installed Incredible PBX 13.2 and FreePBX 13 on different VMs.

It has a SIP trunk through Comcast ADTRAN. This is not and should not be a NAT issue, as the network path should be only VM -> switch -> ADTRAN -> modem/out.
COMCAST has verified that (not this equipment) can make bidirectional calls fine through their equipment.

The Incredible PBX has an issue where, for outbound calls, the call is heard by the recipient (one way) but establishes two way communications after exactly 15-16 seconds. Consistently.

I attempted to use FreePBX 13 to see if different results, and I have one-way audio with no recovery to two way after 20+ seconds.

The NICS are Broadcom, teamed 4x, and I’ll be willing to post any suggested debug information requested.

What can I do to work on resolving one way audio?

“incredible pbx” is 1-2 (major) versions behind. The versioning is confusing but it is a skinned version of FreePBX 2.11 iirc. 1 way audio is typically a nat issue. You likely can see what is happening in either install by watching sip debug. Can you provide a call trace to see if that provides any clues?

OK - I’m not clear on your contention here. When someone uses the phrase “ADTRAN”, it implies that you are either using it as a CSU or a channel bank of some kind. I’m also not used to seeing the word “modem” used to describe the equipment it connects to. AdTran equipment typically connects to carrier-class lines, not consumer connections. Also, I’m not clear how you are getting a SIP trunk through what could be anything from a battery power monitor to a channel bank.

From your description, it’s clear that you are using some kind of NAT and that you aren’t aware that you are, and if that’s the case, you are definitely going to need to supply more information. For example, you used to be able to get two-way audio through the connection after a pause of a few seconds and that doesn’t really surprise me that much. It means that a “start” packet opened up the firewall and made the connection work.

The fact that it doesn’t work like that any more could be any one of a dozen things, most of which were either very tight configuration items or security flaws. It’s possible that you were using “Travelinman” (IIRC) to get around your firewall issues.

@SkykingOH used to be “the man” on IncrediblePBX (or was it PIAF? maybe still is, I stopped paying attention to it) but he does frequent these parts. Lots of the stuff that he’s built into the various distributions of I-PBX and PIAF are now included in the basic FreePBX distro.

Regardless, we are going to need to know more than a few brand names and a vague assurance from a corporation that has proven itself incompetent in the past for us to help you get to the bottom of this.

How did my name get drawn into this?

To be clear Adtran makes a whole line of PoE Switches, routers with SIP SBC’s and SIP to Pots and PRI gateways.

You have a SIP trunk? It terminates to the Adtran box? Is that little network in a private VLAN?

Something is going wrong in the media establishment.

As a Sangoma Gold Partner we provide integration support for FreePBX and the complete line og Sangoma products. As a business I would assume you need quick resolution. One of our certified techs or myself can assist with this.

If you are interested in finding out about our services call 440 385 4150 option 3 or visit our Web site at www.microadv.Com and open a support ticket.

I just wanted to share the fun :smile: