# Buffer and jitter

> Why audio streams keep a buffer, and how Wi-Fi jitter decides how small it can safely be.

Updated 2026-10-06. Canonical page: https://lagless.app/glossary/buffer-and-jitter/

> A buffer is audio sent ahead of time so playback continues if packets arrive unevenly. Jitter is that unevenness. A bigger buffer absorbs more jitter but adds delay; at 350 ms AirPlay keeps 100 ms of buffer after macOS's fixed 250 ms adjust.

Related: [How to reduce AirPlay latency](/guides/reduce-airplay-latency-mac/)