What latency does to remote-agent audio quality

When an agent works from home or a mobile phone, the dialer no longer controls the path the audio takes. Calls cross the public internet, and that path introduces Latency — the time it takes a packet of voice to travel from one end to the other. A small amount is unavoidable. Too much, or the wrong kind, and your agents start talking over the customer or hearing words drop out. This post explains the three things that actually degrade remote-agent audio and how to tell them apart.

Delay, jitter, and packet loss are different problems

Voice on a call travels as a stream of small packets over the RTP protocol — the real-time transport that carries the actual audio once the call is set up. Three separate things can go wrong with that stream, and each sounds different on the call.

• One-way delay is steady lag. At 150 ms one-way it is barely noticeable; past about 250 ms people start interrupting each other because the gap before a reply feels like silence.
• Jitter is delay that varies packet to packet. The receiving end buffers audio to smooth it out, but heavy jitter overflows that buffer and you hear choppy or robotic speech.
• Packet loss is packets that never arrive at all. Even 1 to 2 percent loss produces clipped words and short dropouts, because lost voice cannot be re-sent in time on a live call.

Codec choice trades bandwidth for tolerance

A Codec is the rule the two ends use to compress and decompress the audio. The two you will meet most often on remote agents are G.711 codec, which is uncompressed and uses about 64 kbps per call, and G.729 codec, which compresses down to roughly 8 kbps. G711 sounds cleaner and recovers better from a few lost packets, but it needs more upstream bandwidth — which matters on a home connection running several lines at once. G729 saves bandwidth but is less forgiving when packets drop. Pick based on the agent's real upload speed, not the office one.

How to tell which problem you have

Symptoms point at causes if you know the mapping. People interrupting each other means delay. Choppy or warbling audio means jitter. Words cut in and out means loss. Walk it down in order.

flowchart TD
  A[Audio sounds bad] --> B{What is the symptom}
  B -->|Both talk over each other| C[High one way delay]
  B -->|Choppy or robotic| D[High jitter]
  B -->|Words cut out| E[Packet loss]
  C --> F[Move agent closer or pick a nearer route]
  D --> G[Reduce other home network traffic]
  E --> H[Check the home uplink and switch codec]
  F --> I[Retest a call]
  G --> I
  H --> I

A quick ping from the agent's machine to the server shows both the delay number and how much it varies. If the average is low but the variation is high, you have jitter. If you see dropped pings, you have loss. Most remote-agent audio complaints come down to the home network being busy, so start by closing the streaming and large downloads before blaming the dialer.

Remote agents are only as good as the path their audio takes, so it pays to understand the wider setup in our guide to VICIdial remote agents. If you are deciding between routing through a home softphone or an external extension, the trade-offs in the external phone type explainer are a good next read. And if you would rather not babysit the network at all, our managed plans put the dialer on a tuned, monitored server so the only variable left is the agent's own connection.