Incoming call not ringing but answerable


Good evening all,
I have a strange one, customer is using a mix of Grandstream GXP2130 handsets and Bria softphones with Sennheiser D10 USB headsets on SIP trunks.

99% of calls work correctly, however there is occasionally, 2 or 3 times a day where the Sennheiser headset signals ring in the ear piece but there is no other sign of an incoming call. Bria does not show a call and GXP2130’s do not ring or display incoming call details on the screen.

However if you pickup a GXP2130 hand piece you can answer a call that isn’t ringing, or if you press the answer button on the Sennheiser headset you can answer the call.

I’m not sure if this is related but the Bria softphones do not receive presence information for busy extensions.

Many thanks,


First, replace an existing extension that is now on a softphone with a real IP phone, and see if the problem still arises.
If with the IP phone the problem disappears the problem is located on the Softphone, if the problem remains instead there will be a problem on the settings of the extension side server voip.


What are all the devices connected to, PBX?


The devices are 3 x GXP2130 handset and 4 x Bria softphones.

The issue occurs simultaneously across softphones and IP handsets.

The only indication that there is an incoming call is the ringing in the Sennheiser earpiece but the call can be answered by picking up an GXP2130 handpiece, although the GXP2130 appears to be idle and not ringing.


Sorry, but I understand what the devices are, but I do not know what they are connected to in order to make and take calls. What model of PBX and what firmware on the PBX and phones?


Oh, sorry, it’s been a long day, UCM6204


Did you try to prove that I wrote on it?


Firmware in all???


Bria May 8 2019


I assume that when this occurs, the call is valid, can be answered, has CallerID and a conversation can be had between both ends?

What kind of trunks are in use on the PBX?

OK, the first thing to do is to look in the CDR records and see if you see one (or more) of the calls that came thru without ringing. You may need to tell the client, to make note of the time and callerID so you can pinpoint the call in the CDR and then expand the record to see the path that it took.

The softphone is on a PC and presumably the headset is on the same and therefore controlled by Bria via the PC. How does a call come in in order to reach the extension(s)…ring group, IVR, etc.?