Note: If you have signed up for your account after 24 April 2023, please visit the following article: Troubleshooting Common Call Quality Issues

This article provides the troubleshooting steps for some of the common call connectivity or quality issues you may encounter while taking calls in your phone widget:


The most common scenarios you may encounter are:

  • Call is not connected

  • No audio or one-way audio

  • Call audio has dropouts

  • Call audio is garbled or contains an artifact

Note: Before you start using the phone widget, make sure you test your test connection.



Call did not connect


  1. Ensure your network ports are not blocked by Firewall/router/antivirus software. 

  2. Confirm a network connection is currently available.

  3. Check your browser for Javascript console errors.


No audio or only one-way audio

  1. Ensure your network ports are not blocked by Firewall/router/antivirus software. See network requirements and recommendations for the list of IP addresses ports, and domains to be whitelisted.

  2. Confirm if your headset is correctly connected to your computer.
    Also, ensure that the correct microphone and speakers are selected under sound settings for the input/output devices.

  3. Check to ensure the microphone is not muted (some have a hardware mute button) and the speaker volume is turned up.

  4. If you are using a bluetooth headset, use a USB dongle instead of relying on the computer’s native bluetooth. Retry with a USB headset or a 3.5mm headset and compare the call quality. Since each device behaves differently with each browser, it can be more than a little trouble to tackle such hardware related issues.

  5. Allocate bandwidth for phone with maximum speed and prioritize voice traffic. If possible, allocate distinct bandwidth for each user (based on application/IP address).


Call audio has dropouts

  1. Twilio Client requires a high speed and low latency network connection. Benchmark the network using pingtest.net or speedtest.net and aim to improve the scores.

  2. If your router supports QoS, prioritize UDP ports in the range 10000-20000, and the IP address of the agents making/receiving the calls. See network requirements and recommendations for the list of IP addresses and ports to be whitelisted.

  3. Reduce network activity not related to VoIP or use a separate network for VoIP workstations.

  4. Chrome v38/39 has known issues of audio dropouts / one-way audio. Upgrade your browser or use Firefox and see if the issue persists.

Call audio is garbled

  1. Use an (analog) headset instead of a built-in computer microphone.

  2. Reduce ambient noise such as nearby speakers or fans.

  3. Adjust the distance of the microphone from the mouth – too close can cause audio clipping.

  4. Adjust microphone levels in the computer’s sound settings.

  5. Clear browser cache/cookies

  6. Ensure the computer has resources available to process a call:

    1. Avoid using USB headset and speakers in parallel. This ensures that the CPU and RAM are not over-utilized

    2. Close unnecessary applications and browser tabs

    3. Try disabling the antivirus software and extensions in Chrome


Even after completing the above steps, if the customers face call quality issues, send the following call details to the support team.

    • Form number, 

    • To number 

    • Actual time of the call    

    • Number of agents affected

    • Frequency of occurrence