Troubleshooting: Issues with Zendesk voice

Your connection and environment may cause performance problems when you use web-based software, such as voice or Talk. System or network issues might not appear during regular ticket management but become obvious with a telephony connection. This article provides steps to fix these issues. Before you begin, ask these questions to rule out common issues:

Did voice work before? Check if your IT team changed your network or computer, or added new software or add-ons

Does the issue affect other agents or just you? If the issue affects only you, check your local settings and network. If you and other agents have issues, check with your IT and network teams first, especially if you use a company‑managed laptop

Can agents who use unified agent status take calls? If you use unified agent status, make sure agents have appropriate voice permissions and check the live dashboard to confirm agents appear online for voice calls
See common voice issues:

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voice does not work
voice problems relate to your network. In office setups, network teams block some internet protocol (IP) addresses or ports. Ask your network team to confirm that you meet all voice network requirements. For more information, see Voice network requirements.
To perform these checks:

Check the Zendesk and Twilio status pages for outages
Check the Agent leg quality issues report in Explore to identify call quality issues on your team and with specific agents

Fix voice quality issues
Use these checks to fix call quality:


Ask your IT team whether your voice traffic goes through a virtual private network (VPN). If it does, make sure voice traffic does not go through your company network. Your IT department can split-tunnel this traffic or remove the Zendesk IP addresses from the VPN.
voice does not work with multiprotocol label switching (MPLS) or VPN due to Twilio's edge network architecture requirements.

Run the Twilio network test to confirm ports are open, speed is adequate, and you connect to the right endpoint. To use these results, see How to use the Twilio network test to troubleshoot voice agent calls?

Connect your computer to your router with an Ethernet cable. Wi‑Fi works, but Ethernet is stable because other wireless devices can interfere with the signal
Try a different web browser to rule out a browser issue
Connect your headset to the computer with a 3.5 mm cable instead of Bluetooth. A universal serial bus (USB) connection is better than Bluetooth. Other wireless devices and signals degrade audio. To rule out the headset as the cause, use your computer speakers and make a test call
If you use a gaming headset, deactivate its audio driver software. It's not supported and causes issues with Talk. Sometimes browsers, such as Chrome, don't synchronize fast enough in this situation
Make sure your internet connection is stable. If your web browser passes the Twilio test and you still have issues, your connection might be unstable. You might drop network packets or have a connection that slows down at times. Your IT or network team can run software over time to measure stability. Do this yourself only if you feel comfortable and your company's IT department allows it

To see how stable your internet connection is:

If you are at home, reboot your router
Run a ping test for 10 to 15 minutes, especially when you have problems. Check for stability and packet loss. See the image below for a short example of the test results

In addition to www.zendesk.com, test the Twilio client endpoints with a ping test

Make sure the ping time in ms is adequate and stays consistent. In most cases, you want zero packet loss. If you see as much as 1% packet loss in 15 minutes, this might affect your connection. voice with your IT department or contact your internet service provider for help.
Network connectivity test endpoints
Endpoint URLs may be updated by Twilio. Verify against current Twilio documentation before you configure firewalls or network policies.
Make sure the ping time in ms is adequate and stays consistent. In most cases, you want zero packet loss. If you see as much as 1% packet loss in 15 minutes, this might affect your connection. voice with your IT department or contact your internet service provider for help.
Dropped calls If calls drop after two minutes, check with your admin. You might use a trial account. voice trial accounts limit calls to two minutes. If calls drop every time you call one of your numbers and you use an interactive voice response (IVR) setup, create a custom greeting. Without a greeting in the right IVR menu locations, the system hangs up. If you already have a greeting, a corrupt audio file can cause the same behavior. Re-record the audio file and upload it again to rule this out. EC# error
See an <EC#> error example:
EC# errors often come from your network or router configuration. They indicate that voice doesn't have an adequate network connection. This can occur anywhere on the network, but it often results from local network limits or from a computer that doesn't meet the minimum requirements to make the connection. Review the voice network requirements. Ensure all ports are open. Also review the steps above. If you still experience EC# errors, Contact Zendesk Customer Support for further help.
For more information on what to include in a ticket about Talk, see How can I share example calls for troubleshooting a voice issue?
Call status issues If you refresh your page, your agent status might change to unavailable in Talk. An agent needs to manually reset their voice agent state to become available. Do not refresh your browser page when you want to receive calls. If you can't determine the cause of your quality issues and your issue is specific to call routing, see Why are phone calls not routing to agents?