Incoming Calls Collide with Each Other


Sorry that I misinterpreted the log. Unfortunately, I know almost nothing about Sangoma phones. I know that if you blind transfer an incoming call to 71, it gets parked. If you then attended transfer another incoming call to 71, that unparks the first call and the two incoming calls are connected together.

You could use pjsip logger to see the SIP transactions that underlie whatever buttons were intentionally or accidentally pressed. When a phone is ringing, what options are presented? If one of the options is ‘forward’ or ‘reject’, that may have been preprogrammed to effect a park action. Or, if you have a parking BLF key set up, it’s possible that pushing that while the phone is ringing will park the unanswered call.

If all else fails you can make some test calls in and see if any option results in answering the call and immediately parking it.

(David55) #22

I meant that it was expecting to find a particular call parked in the slot but a different call was actually parked there.

Something must have parked a call in slot 71. I meant find out, from the logs, what put the call there.

The call is being specifically redirected to pick up the call from slot 71.

That’s not physically possible; the data structures can only store one channel.

It appears that the extensions involved in your two log fragments have call forward unconditional set to 71 (I suppose it could be call forward busy, if the phone can do that). That doesn’t seem a sensible thing to do.

It also seems likely that another device is set to do similarly to the park a call virtual extension (which I guess is 70).

The “forwarding thanks to …” message indicates, for chan_sip, that the phone returned a SIP 302 Moved Temporarily response, together with a new extension number to call, which is how a phone would implement unconditional (or possibly busy) forwarding.


Thank you for helping me track this down. May I assume that the offending extension is in Ring Group 420? I’ll look into the call forwarding thing a bit more. It is disabled via the extension manager in the web interface. How can I get 451 to not be a Zulu extension.

(David55) #24

I’m talking about the phone itself. The S505 has a native call forwarding feature that doesn’t require FreePBX. Looking at the S Series user guide, details are on page 21 (PDF page 31). This is for Revision 1, from April 2017, of the user guide.

It is possible there are also ways of changing this remotely, but someone else will need to chip in with those.


Thank you for all your help! I plan to look at extension 451 as soon as I return to the office.
I just called and experienced what I had indicated earlier for an employee. If I am reading this right, extenstion 421 (uses a headset) answers the call and then does something that hangs up. Am I interpreting this correctly?

Here is the log: Answer / Hangup

(David55) #26

In virtual extension 420 causes, amongst others, 451 to be called. 451 doesn’t answer, but instead forwards the call to 71, using SIP forwarding, rather than FreePBX forwarding.

In 421 answered the call, and 28 seconds later, one side or the other ended the call. There isn’t enough detail to see why, but 28 seconds is a typical timeout for failing to receive an ACK from Asterisk, in response to OK from the phone, which often happens with broken NAT or over zealous firewalls. This should be clear from pjsip set logger on, and probably also so if you turn up the verbosity.


In , the call was answered on extension 421 at 09:28:17. Unfortunately, the log ends within that second, so the section related to the trouble is not present.

BTW, when you paste logs, we prefer you to use . It’s ok to post content on another service, but be sure that the expiration is set to ‘never’, so future readers of the thread can follow along. Don’t post content on a server with enforced expiration, or one that requires the reader to log in (and be tracked). If you have content that cannot be posted directly here or pasted, make a .tgz file and attach it to your post.


Thank you. Armed with the information contained within the logs, I had a discussion with my reception team who thinks they may be hitting a horizontal soft key button (specifically the transfer) sometime when they answer. I would like to disable it, but I can’t figure out how to set it in EPM. I set the button, but the phones don’t revert back to what they had before - the changes are not reflected on the phones. I posted this problem in the phone forum a couple of months ago and did not hear back. Link to other discussion

I originally bought the Sangoma Phones to support the company that is making FreePBX possible. After having this problem and another, I’m starting to regret that purchase .
If the problem persists, I’ll look at a pjsip log to see if we can tell what buttons are being pushed. I need a very basic “how to” on this. My searches have turned up some instructions, but they assume I already have a CLI on the phone. Is there a piece of software I need to install?

(system) closed #29

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