If your call participants are seeing packet loss, during a call, recommend that they try:
Rebooting your computer
Moving closer to your WiFi router
Or, if possible, connecting via Ethernet
Test your packet loss by visiting, https://network.callstats.io
What is packet loss?
Packet loss is different from your speed test or download speed. Packet loss reflects UDP data, which is the data transmitted when you stream live media.
When streaming live media network issues often relate to an OS-level root cause. That's why, if you're having issues, rebooting often is a smart thing to try.
See our 2020 update above.
Video calls need a good connection. Because a video call streams live media, having a fast internet connection is not enough.
Traditional speed tests look only at TCP data, which are used for downloads. For example, a speed test might give you a good sense how quickly you can download a file off of a website.
In contrast, video calls use UPD live media streaming. Data is not buffered.
Here's an example. When you're watching Netflix, you are not streaming live media. Your device is buffering the content you're downloading. This can't be done during a video call because the data you're streaming is live.
It's not unusual for a user to have a great network, but experience packet loss on a call. Network congestion, firewall barriers, and/or old or affected hardware (like a router that needs rebooting) can play a role.