Jitter vs latency: why the call sounds bad when ping looks fine

Latency is how long a packet takes. Jitter is how much that time jumps around. Real-time audio has a tiny buffer. When arrival times swing, the buffer underruns and you hear robotic audio, dropped syllables, or a frozen tile with a voice that keeps going.

That is why “my ping is 25 ms” can be true and the call can still be unusable. The average hid the swings.

A practical way to read jitter

• Low and steady: calls and games feel consistent even if the absolute ping is not tiny.
• Medium (around 30 ms, a common ITU-T ballpark): you will notice it on voice before you notice it on a web page.
• High or spiky: Zoom will sound drunk. First-person games will rubber-band.

Common sources on a home Mac

Congested Wi-Fi, a sibling starting a 4K stream, bufferbloat on a cheap router, a VPN, or an ISP path that is not lossy but is uneven. PingStatus can treat jitter as part of connection health, and version 2.1.2 lets you pick Low / Medium / High sensitivity or turn jitter-based health off if you only want loss and latency.

What to do about it

Ethernet beats Wi-Fi for meetings. Pause large uploads. If the gateway is calm and the public target jitters, the problem is not your laptop. If only the gateway jitters, you have a local radio or router problem.