The culprit hunt
Who is echoing? Find the source on a group call
Eight people on a call, everyone hearing their own voice bounce back, everyone checking their own settings — and precisely one device in the group is doing it. Group-call echo always has a single source (occasionally two), and it can be located in about two minutes with a method that works identically in every meeting app, because it uses no app features at all beyond mute. No blame, no twenty-minute audio séance. Here's the procedure.
Two facts narrow it before you start: First — the person causing the echo usually doesn't hear it. Their device replays everyone else's voices into their mic; they never hear a copy of themselves, everyone else does. The participant cheerfully saying "sounds fine to me" is your lead suspect. Second — whoever does hear the echo is (almost always) innocent; a device can't re-transmit to its own ears. The logic behind both is in the echo diagnostic.
Shortlist first (30 seconds)
Before methodical muting, sweep for the usual suspects — one of these is the answer most days:
- Anyone on open speakers or speakerphone — laptop speakers at volume, a phone flat on a desk, a car system. Speakers feeding a mic is the entire crime; no-speaker participants (headphones/headsets) are near-incapable of it.
- Anyone joined twice — laptop plus phone on the same meeting, or a browser tab and desktop app both connected. Two sessions in one room is a guaranteed loop.
- Two participants in one physical room, each on their own device with live audio.
- The person who reports no echo at all while everyone else suffers (see above).
Ask the shortlist to drop volume or mute for ten seconds. Echo gone? Done — jump to the fix list below. Nothing obvious? Run the method.
The mute-in-turn method (two minutes, any app)
- Appoint a caller. Anyone who hears the echo clearly. They'll talk continuously — counting out loud works — because the test needs constant speech to bounce.
- Mute one participant at a time. Ten seconds each, in any order (shortlist first). A host who can mute others makes this fast; without one, people self-mute on request. The muted person's speakers stay on — only the mic matters.
- Listen for the silence. The moment the echo dies, the last-muted mic is your device. Unmute them and confirm: echo returns → confirmed. (Do confirm — coincidences happen when two people fiddle with settings simultaneously.)
- If muting everyone-but-the-caller never kills it, the caller's own audio path is looping locally (rare, but virtual devices do it — sudden-echo checklist), or two culprits overlap: repeat once with the first culprit left muted.
Why is it always just one device? Because a loop requires a specific coincidence — speakers loud enough, a mic near enough, and a canceller failing — and that coincidence is rare enough that two participants hitting it in the same meeting almost never happens. This is also why "everyone check your audio" is such a wasteful instruction: it sends seven innocent people into their settings while the eighth, who hears no problem, changes nothing. Point the procedure at the call, not the crowd, and the odds do the work for you.
You found them. Now what?
Say it without ceremony — "found it, it's your device, super common, ten-second fix" — and hand them, in order:
- Speaker volume down a third. Their canceller was probably nearly coping; this tips it back over the line.
- Mic away from speakers, if it's parked in front of them.
- Kill the second device if they're double-joined — leave the call on one of them, fully.
- Earbuds if they have them handy — instant end of their loop, zero settings.
- A cancellation layer if this is chronic. The colleague who echoes every single week on open speakers is the textbook case for dedicated echo cancellation software — the free tiers mean they can fix it before the next standup without spending anything.
The full versions of these fixes — with the reasons they work — are in the no-muting playbook.
Make the next hunt unnecessary
- Normalize the two-minute hunt. Teams that treat "quick echo check" as routine spend less total time on audio than teams that mute everyone forever. The method is app-agnostic on purpose — it survives every platform migration your company will ever do.
- Remember the asymmetry. "I hear echo" = someone else's loop. "They hear echo" = possibly yours. Half of all echo blame is aimed backwards, and it wastes everyone's checklist time.
- A howl instead of an echo? Same circuit, runaway version, and the hunt is even easier — it's nearly always two devices in one room. The feedback page covers it.