Troubleshoot Call Quality Issues

Troubleshooting3 min readUpdated 2026-03-12

Troubleshoot Call Quality Issues

If your calls have echo, choppy audio, one-way audio, or noticeable delay, use this guide to identify and fix the problem.

Available on: All plans


Identify the symptom

SymptomLikely causeFirst step
EchoSpeaker audio feeding back into microphoneSwitch to a USB headset
Choppy or robotic audioInsufficient bandwidth or high packet lossClose bandwidth-heavy apps and run a network test
One-way audio (you hear them, they don't hear you)Microphone permission blocked or wrong device selectedCheck browser microphone permissions
One-way audio (they hear you, you don't hear them)Speaker output set to wrong deviceCheck audio output in JustCall settings
High latency / delayNetwork congestion or VPN routingSwitch to a wired connection and disable VPN

Check your network

JustCall calls require a stable internet connection. Minimum requirements:

  • Bandwidth: 100 Kbps upload and download per concurrent call (1 Mbps+ recommended)
  • Latency: Under 150ms round trip
  • Jitter: Under 30ms
  • Packet loss: Under 1%

Run the built-in network test: Go to Settings > Network Test > Run Test. If results are below these thresholds, contact your IT team or switch to a wired Ethernet connection.


Check your browser and audio device

  1. Use Google Chrome (latest version) for best compatibility.
  2. Go to chrome://settings/content/microphone and confirm JustCall has permission.
  3. In JustCall, go to Settings > Audio and verify the correct microphone and speaker are selected.
  4. Test with a different headset to rule out hardware issues.
  5. Close other tabs or applications using your microphone (Zoom, Google Meet, etc.).

Required ports and domains

If your network has a firewall, ensure the following are open:

TypeValuePurpose
UDP ports10000-60000Voice media (RTP)
TCP port443Signaling and API
Domains*.justcall.io, *.twilio.comApplication and voice infrastructure

Ask your IT team to prioritize UDP traffic with QoS settings for the best call experience.


Still experiencing issues?

  1. Clear your browser cache and cookies.
  2. Restart your browser.
  3. Try an incognito window to rule out extension conflicts.
  4. If the problem persists, download network logs and submit them with a support ticket.

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