Jitter

Packets in a call should arrive at steady intervals. Congested links, Wi-Fi retries and overloaded devices make them bunch up and spread out instead. Phones and apps hide a little of this with a jitter buffer that briefly holds packets to even them out, but a large buffer adds delay and a small one drops packets, so the cure for serious jitter is the network, not the buffer.

For a growing business jitter is usually the first sign that the network has outgrown its design: more people on the same Wi-Fi, a switch that is now also carrying cameras and backups, or an internet uplink that is saturated at busy hours. Because it comes and goes, it is often dismissed until customers mention it.

Ask your network partner to measure jitter, latency and packet loss over a working week rather than in one test, to show where on the path the variation appears, and whether QoS is prioritizing voice on the congested links. Ask your phone or meeting provider what jitter their service tolerates and what their dashboards report per call.