Troubleshooting: Issues with Zendesk voice

<p>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.</p><p>Before you begin, ask these questions to rule out common issues:</p><ul>
<li data-list-item-id="e5cd75093a23babd20687fbae82f46d06">
<strong>Did voice work before?</strong> Check if your IT team changed your network or computer, or added new software or add-ons</li>
<li data-list-item-id="ea60ec87eeed23467eb36fe1b23e431e9">
<strong>Does the issue affect other agents or just you?</strong> 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</li>
<li data-list-item-id="e8cb5eb74ece19b26d54a6419603bb20a">
<strong>Can agents who use unified agent status take calls?</strong> If you use <a href="https://support.zendesk.com/hc/en-us/articles/5133523363226-About-unified-agent-status" target="_blank" rel="noopener noreferrer">unified agent status</a>, make sure agents have <a href="https://support.zendesk.com/hc/en-us/articles/4408882966170-Giving-agents-access-to-Talk" target="_blank" rel="noopener noreferrer">appropriate voice permissions</a> and check the <a href="https://support.zendesk.com/hc/en-us/articles/4422485166746-Seeing-live-agent-status-and-activities-with-Explore" target="_blank" rel="noopener noreferrer">live dashboard</a> to confirm agents appear online for voice calls</li>
</ul><p>See common voice issues:</p><div style="margin-bottom: 20px; text-align: right;">
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</script><div class="accordion"><p>voice does not work</p></div><div class="panel">
<p>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 <a href="https://support.zendesk.com/hc/en-us/articles/4408831417498-Talk-network-requirements" target="_blank" rel="noopener noreferrer">Voice network requirements</a>.</p>
<p>To perform these checks:</p>
<ul>
<li data-list-item-id="e597bb57ffe264a1fd015b3ae915f0376">Check the Zendesk and Twilio status pages for outages</li>
<li data-list-item-id="eeb75c3f7016aacb1b180897aaa7342fa">Check the <a href="https://support.zendesk.com/hc/en-us/articles/4408836253338-Analyzing-your-Talk-activity#topic_fpx_stt_mmb">Agent leg quality issues</a> report in Explore to identify <a href="https://support.zendesk.com/hc/en-us/articles/4408833546522-Reporting-on-Talk-network-and-audio-quality" target="_blank" rel="noopener noreferrer">call quality</a> issues on your team and with specific agents</li>
</ul>
</div><div class="accordion"><p>Fix voice quality issues</p></div><div class="panel">
<p>Use these checks to fix call quality:</p>
<ul>
<li data-list-item-id="e931a8d47efaeb9820c485f93428f816c">
<p>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 <a href="https://www.security.org/vpn/split-tunneling/" target="_blank" rel="noopener noreferrer">split-tunnel</a> this traffic or remove the Zendesk IP addresses from the VPN.</p>
<div class="note"><p>voice does not work with multiprotocol label switching (MPLS) or VPN due to Twilio's edge network architecture requirements.</p></div>
</li>
<li data-list-item-id="e287af058e97976188c41dbca765f2fbe">Run the <a href="https://networktest.twilio.com/" target="_blank" rel="noopener noreferrer">Twilio network test</a> to confirm ports are open, speed is adequate, and you connect to the right endpoint. To use these results, see <a href="https://support.zendesk.com/hc/en-us/articles/4408823183002" target="_blank" rel="noopener noreferrer">How to use the Twilio network test to troubleshoot voice agent calls?</a>
</li>
<li data-list-item-id="e4bd08d805ff8dea4c333fd01f9851932">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</li>
<li data-list-item-id="e7f7776e235076d9afdcc52ef9873a6ff">Try a different web browser to rule out a browser issue</li>
<li data-list-item-id="e7d02ae71db4c4e9391cba1590babbfb0">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</li>
<li data-list-item-id="e9d1fb822d8d6f08a104a65107ac8779a">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</li>
<li data-list-item-id="e55d846060ddea788e3e88058c334a588">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</li>
</ul>
<p>To see how stable your internet connection is:</p>
<ol>
<li data-list-item-id="e210303200cc039c8bd9015b1b6c2cb02">If you are at home, reboot your router</li>
<li data-list-item-id="e2d86192b19eeb729f9ca025a62e36a35">Run a <a href="https://kb.netgear.com/989/Testing-network-connectivity-with-ping" target="_blank" rel="noopener noreferrer">ping test</a> 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 <img src="https://support.zendesk.com/hc/article_attachments/10878227300122" alt="Ping test results" width="500px">
</li>
<li data-list-item-id="e94b110e9f79598baf09241574c62009e">In addition to www.zendesk.com, test the <a href="https://www.twilio.com/docs/voice/client/javascript/voice-client-js-and-mobile-sdks-network-connectivity-requirements#signalling-connectivity-requirements">Twilio client endpoints</a> with a ping test</li>
</ol>
<p>Make sure the ping time in <code>ms</code> 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.</p>
</div><div class="accordion"><p>Network connectivity test endpoints</p></div><div class="panel">
<div class="p">
<p data-path-to-node="10">If you troubleshoot issues related to the Zendesk Talk Twilio Voice Software Development Kit (SDK), ensure your network allows traffic to the necessary endpoints:</p>
<ul data-path-to-node="13">
<li data-list-item-id="e86741a36e56d9023c1122aa4fa2a47e5"><p data-path-to-node="13,0,0"><code data-path-to-node="13,0,0" data-index-in-node="0">chunderw-vpc-gll.twilio.com</code></p></li>
<li data-list-item-id="e340f4b834725533f50f7007ff22aa806"><p data-path-to-node="13,1,0"><code data-path-to-node="13,1,0" data-index-in-node="0">chunderw-gll.twilio.com</code></p></li>
</ul>
<p data-path-to-node="11">For the most current list of Twilio Voice SDK network requirements and test endpoints, see <a href="https://www.twilio.com/docs/voice/sdks/network-connectivity-requirements" target="_blank" rel="noopener noreferrer"><strong data-path-to-node="11" data-index-in-node="119">Voice SDKs Network Connectivity Requirements</strong></a>.</p>
</div>
<div class="p"><div class="note">
<span class="notetitle">Note:</span> Twilio may update endpoint URLs. Always verify against current Twilio documentation before you configure firewalls or network policies to avoid false negatives in network diagnostics or incorrect allowed IPs.</div></div>
</div><div class="accordion"><p>Dropped calls</p></div><div class="panel"><p>If calls drop after two minutes, check with your admin. You might use a trial account. <a href="https://support.zendesk.com/hc/en-us/articles/4408823792922-Is-there-a-difference-in-functionality-between-Talk-trials-and-subscribed-Talk-plans-" target="_blank" rel="noopener noreferrer">voice trial accounts</a> limit calls to two minutes. If calls drop every time you call one of your numbers and you use an <a href="https://support.zendesk.com/hc/en-us/articles/4408885628698-Routing-incoming-calls-with-IVR" target="_blank" rel="noopener noreferrer">interactive voice response (IVR) setup</a>, 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. <a href="https://support.zendesk.com/hc/en-us/articles/4408825862938-How-do-I-add-a-new-greeting-" target="_blank" rel="noopener noreferrer">Re-record the audio file</a> and upload it again to rule this out.</p></div><div class="accordion"><p>EC# error</p></div><div class="panel">
<p>See an <code>&lt;EC#&gt;</code> error example:</p>
<figure><p><img src="https://support.zendesk.com/hc/article_attachments/10878170475546" alt="EC5 error message" width="500px"></p></figure><p><code>EC#</code> 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 <a href="https://support.zendesk.com/hc/en-us/articles/4408831417498-Talk-network-requirements" target="_blank" rel="noopener noreferrer">voice network requirements</a>. Ensure all ports are open. Also review the steps above. If you still experience <code>EC#</code> errors, Contact Zendesk Customer Support for further help.</p>
<p>For more information on what to include in a ticket about Talk, see <a href="https://support.zendesk.com/hc/en-us/articles/4408825659162-How-can-I-share-example-calls-for-troubleshooting-a-Talk-issue-" target="_blank" rel="noopener noreferrer">How can I share example calls for troubleshooting a voice issue?</a></p>
</div><div class="accordion"><p>Call status issues</p></div><div class="panel"><p>If you refresh your page, your agent status might change to unavailable in Talk. An agent needs to manually reset their <a href="https://support.zendesk.com/hc/en-us/articles/4408829114138-Setting-your-Talk-agent-state" target="_blank" rel="noopener noreferrer">voice agent state</a> to become available. Do not refresh your browser page when you want to receive calls.</p></div><p>If you can't determine the cause of your quality issues and your issue is specific to call routing, see <a href="https://support.zendesk.com/hc/en-us/articles/5176192218522-Why-are-phone-calls-not-routing-to-agents-" target="_blank" rel="noopener noreferrer">Why are phone calls not routing to agents?</a></p>