How to troubleshoot issues with inbound/outbound calls and call quality.
IMPORTANT: This article is primarily aimed at issues with physical SIP phones, if you have an issue with any of the apps the information here may not all be relevant, please check their specific articles for more information.
Devices cannot make calls.
- Reboot the device/do basic end user checks.
- Check the call history, does the call show in the call history?
The call shows in the call history.
- Check that the emergency caller ID of the user is configured correctly. A misconfigured emergency caller ID will be rejected by the trunk.
- Double check config of the domain, ensure that the user is set to be able to call the destination they are dialling.
- Get a sip trace and submit a ticket to help.luminatewholesale.com.
The call does NOT show in the call history.
Try forcing the codec to PCMA/PCMU only or register the phone over TCP instead of UDP (or the other way round if TCP is already set).
If this does not fix the issue and the issue is only happening to this site, then the problem is almost certainly a network related issue. Please refer to our guide on troubleshooting network issues.
Devices cannot receive calls.
If phones aren't ringing when you ring a number, or the number just plays an error tone, then the first thing you need to check is if the call shows in the call history.
The call does not show in the call history.
The majority of inbound call issues are caused due to a misconfiguration of the number in the inventory.
The number must be added with "44" at the beginning instead of "0". For example, the number "443331887878" is valid, "03331887878" is not.
IMPORTANT: Numbers added to the inventory are automatically formatted to show with a 0 at the front, this means that numbers added with both "44" and "0" will still look the same in the Inventory.
To ensure it's configured correctly, delete the number from the inventory and then add it back again.
If the call still does not come through and still does not show in the Inventory, please raise a ticket to the support team.
The call shows in the call history.
Open the SIP trace the call, at some point in the call you should see an "INVITE" being sent to the listed device, it will look similar to the below:
If the invite exists, it means that there is a network/hardware issue as our platform has dispatched the call to the phone, but the phone is not receiving/processing it. As such please refer to this article.
If the invite does not exist then first point the DDI directly at the affected user (only do this step if the user is in a ring group/queue or comes after an auto attendant), if the user rings then the issue will be with the configuration.
If it doesn't ring, then check the SIP trace for the invite as above, if there is still no invite then raise a ticket to our support team with a copy of the trace.
Cannot Receive Calls from Certain Numbers
If a certain number cannot receive calls from certain numbers or certain types of numbers (such as "all mobile numbers") then the issue is most likely a carrier issue.
When a number ports number carriers can rarely miss routing updates which can cause calls between certain carriers to fail.
Raise this to the support team.
TIP: If you can, find out the who the telecoms provider is for the numbers that are failing to call, the issues are likely between the carriers and knowing which carriers are failing can vastly speed up the issue being fixed.
Calls Dropping Mid Call
The biggest cause of this is a short UDP timeout (see here).
If you can't change the UDP timeout then you can also try running the phones on TCP or TLS instead.
If neither of these fix it then the issue is likely a network/hardware issue.
Poor Call Quality on Calls
Unless the call quality issues are on multiple sites then call quality issues are always network related.
For this check for low MOS scores. A low MOS score indicates a network problem.