Video call echo and audio troubleshooting
Start with who hears the problem. That tells you which room to fix.
Showing all symptoms.
First rule: echo is heard at the far end, caused at the near end
If remote people hear themselves echoing, the problem is in your room: your mics are picking up their voice from your speakers and sending it back. If you hear echo of your own voice, the problem is in the remote room. Fixing the wrong room is the most common wasted hour in conferencing support.
Remote people hear themselves echo
- The echo canceller has no reference, or the wrong one. AEC needs the far-end audio that goes to your speakers as its reference. If the reference is the wrong channel, missing, or taken from a point that doesn't match what the speakers play, it can't cancel anything.
- The speakers are too loud or distorting. An echo canceller models a clean, linear path from speaker to mic. Clipping amps and rattling speakers break that model. Turn the room down before turning the mics down.
- A mic sits too close to a speaker. Ceiling mics right next to ceiling speakers, or a tabletop mic in front of a sound bar, swamp the canceller.
- Echo only on some calls or devices? Check whether a laptop joined the meeting in the same room with its own mic and speakers open. That's an echo path the room system can't see.
The room sounds hollow, warbly or underwater
- Double processing. Echo cancelling, noise suppression and auto gain running in both the room's DSP and the meeting software, or in a USB mic and the software, fight each other. Pick one place to do each job and turn it off in the other.
- Too many open mics. Several mics hearing the same talker at slightly different times combine into a comb-filtered, roomy sound. An automixer that gates unused mics fixes it.
- A live, echoey room. Hard walls, glass and bare tables make the voice reach the mic many times. Acoustic treatment helps more than any DSP setting.
Echo appears a few seconds into a call, or after a volume change
- The canceller is re-converging. AEC learns the room as the call goes. Big jumps in speaker volume or moving a mic make it re-learn. A short burst of echo that settles is normal; echo that never settles isn't.
- The AEC reference is taken before the room volume control. Take the reference after the volume control, as close to the amplifier feed as possible. If the room volume changes after the reference point, the reference no longer matches what the speakers play.
Remote people say the room is too quiet or distant
- Talkers are outside mic coverage. Check where people actually sit against the mic layout. Use the ceiling mic coverage calculator.
- Gain staging. Mic preamp gain too low, and then auto gain pumping up the noise. Set the preamps so normal speech sits at a healthy level before any processing.
- The meeting software's own auto gain is fighting the room DSP. Same fix as double processing.
Audio is choppy, robotic or cuts out
- That's usually the network, not the audio system. Packet loss and jitter sound robotic and choppy. Check the meeting platform's call statistics before touching the DSP.
- USB problems cause clicks and dropouts too: long or passive USB extensions, hubs sharing bandwidth with cameras, and power-saving modes that sleep the port.
Hum, buzz or constant noise
- Ground loops between the DSP, the display and the PC show up as 60 Hz hum (50 Hz outside North America). Check balanced connections and shield (pin 1) wiring before reaching for isolators.
- HVAC and projector fans right next to ceiling mics. Noise suppression can hide it, at a cost to voice quality. Move the mic first.