Acoustic Echo Cancellation: Setup and Troubleshooting

Acoustic echo cancellation (AEC) targets sound from a speaker that returns through a microphone. It is different from listening ANC and general background-noise suppression. Start by finding the playback-to-microphone loop before buying equipment or adding processing software.

Why You Hear Your Own Voice

Your voice can play through another participant's speakers and be captured by their microphone, returning to you after a delay. If you hear your own voice, the source may be at the other end. If several devices in the same room join with active microphones and speakers, they can also create a loop.

What AEC Software Does

AEC uses the playback signal as a reference to reduce the returning echo in captured audio. The WebRTC audio-processing requirements discuss endpoint echo control and the difficulties created by different capture and playback clocks. That is a processing requirement, not proof that every app or headset implements the same algorithm.

Microsoft documents echo cancellation in Teams. This does not establish a universal Windows 11 AEC switch available on every sound device. Device enhancements depend on the driver and hardware, while meeting applications may process their own audio.

Test the Loop in Order

1. Ask which participant hears the repeated voice. Temporarily mute microphones one at a time to identify the returning path.
2. Keep one active microphone/speaker pair per room. Join additional devices without meeting audio.
3. Select the intended microphone and output in the app and operating system.
4. Lower speaker volume and separate the microphone from the speakers. Try a headset to reduce acoustic coupling.
5. Disable unnecessary monitoring or duplicated audio routes, then repeat the test.
6. Check the app's documented processing and device driver before stacking third-party effects.

Microsoft's Teams sound-sharing guidance also explains how to avoid multiple active audio devices in a meeting room. Shared system sound and microphone sound are different paths.

If the Echo Remains

Test a local microphone recording and then a call. A clean local recording with echo only in one meeting points toward the meeting route or another participant, rather than proving your headset is defective.

For missing or incorrect microphone input, use the headset microphone troubleshooting guide. For desk-phone wiring, use the desk-phone compatibility guide instead of installing PC software to solve an unrelated telephone connection.