Background noise
Most background noise is the room reaching an open mic. Fix the room and the mic distance first, then let the app's suppression clean up the rest.
- Room · source off
- Mic · closer mic
- System · input volume
§ Apps · Slack (huddles)
Slack (huddles)
Quick audio and video huddles in any Slack channel or direct message.
- Platforms
- Windows · macOS · iOS · Android · Web browser
- Suppression
- Noise suppression
- Echo cancel
- No setting listed
- Noise gate
- No setting listed
- Push-to-talk
- Yes
- Last verified
- 2026-10-18
§ 01 — Setting
Where the setting is
| Platform | Path |
|---|---|
| Windows | Profile picture → Preferences → Audio & video → Microphone (noise suppression is one of the microphone options) |
| macOS | Profile picture → Preferences → Audio & video → Microphone (noise suppression is one of the microphone options) |
| iOS | Slack's help lists no noise setting for the mobile app; in a huddle, the three-dots menu has speaker and push-to-talk options |
| Android | Slack's help lists no noise setting for the mobile app; in a huddle, the three-dots menu has speaker and push-to-talk options |
| Web browser | Profile picture → Preferences → Audio & video → Microphone (noise suppression is one of the microphone options) |
One of your huddle microphone preferences; Slack says it removes background sound. Next to it, automatic gain control keeps your voice at a steady level for the people you are talking with.
§ 02 — Layers
The three layers
Noise can be fixed at three points before it leaves you. Start at the top: a fix at the device beats any amount of software.
| Layer | What it does | What to set |
|---|---|---|
| L1 · Device | The mic and where it sits. Distance to your mouth sets how loud your voice is against the room. | Pick the right mic in the app. A headset or a mic close to your mouth beats a laptop mic across the desk. |
| L2 · System | Your operating system passes the mic to the app at the input volume you set, sometimes with its own processing. | In your system sound settings, choose the same input device and set its volume so speech stays in the green on the noise test. |
| L3 · App | Slack (huddles) cleans the signal before it sends it: Noise suppression. | Profile picture → Preferences → Audio & video → Microphone (noise suppression is one of the microphone options) |
Echo cancellation. Slack's huddle help lists no echo setting.
Noise gate. Slack's huddle help lists no gate. Automatic gain control evens out your level; it does not cut the mic between words.
§ 03 — Limits
What it cannot fix
- Slack documents noise suppression in the desktop preferences only, not in the mobile app.
- In a browser, huddles work in Google Chrome (Mac, Windows and Linux) and Firefox (Mac and Windows).
- In a huddle with many people, Slack suggests turning off noise suppression or your video if things slow down.
- The audio, video and screen sharing test works only in the desktop app and in Chrome.
- On Windows 10, Slack cannot detect a headset that is not the system default device.
- On the free plan a huddle holds two people.
§ 04 — Symptoms
Fixes for what you hear
Echo
Echo is almost always someone's speakers playing the call into their own mic, and the person causing it usually cannot hear it.
- Room · headphones
- Room · one device per room
- Room · TV down
Laptop mic picks up typing
A laptop's built-in mic sits in the same case as its keyboard, so a headset or external mic helps more than any setting can.
- Mic · headset
- Mic · external keyboard
- System · system filter
Mic too quiet
A quiet mic is usually distance, the wrong input device or a low input volume in the system, not a broken mic.
- Mic · closer
- Mic · right input
- System · input volume
Voice cutting out
Clipped first words almost always mean a voice activation threshold set too high. Dropouts mid-sentence point to the connection or Bluetooth.
- Mic · closer
- Mic · USB headset
- App · threshold
Others hear themselves
If others hear themselves when you unmute, the echo is on your side: your speakers, a second device or your sound driver sends their voices back.
- Room · headphones
- Room · one device
- Room · one audio source
Robotic voice
A robotic voice is usually late or lost packets on the network, or a headset sending audio at a rate the app does not expect.
- Mic · USB headset
- System · separate devices
- System · close apps
One-sided audio
One-sided audio is almost always a mute, a blocked mic permission or the wrong device, in that order. Firewalls come last.
- Mic · unmute
- Mic · one device
- System · mic permission
Bluetooth mic sounds bad
Classic Bluetooth drops to a narrow, mono call mode whenever its mic is on. A separate mic, or LE Audio, avoids the switch.
- Mic · separate mic
- Mic · one device
- Mic · AirPods mic
Delay and lag
Most call delay comes from the network: a distant server, busy Wi-Fi or a VPN. Some apps add a little delay of their own.
- App · push to talk
- App · video off
- Network · VPN off
§ 05 — Test
Test it
The noise test rates your mic fine for Slack (huddles) when your noise floor is at or below −50 dBFS and your voice is at least 20 dB above it. Between −50 and −40 dBFS it is usable with suppression on; above that, the noise needs fixing at the room or the mic.
These bars are our rule of thumb for how much steady noise Slack (huddles)'s built-in suppression copes with, not figures from Slack (huddles). The methodology explains them.
Test my mic for Slack (huddles) → § 06 — Questions
Slack (huddles) questions
Q.01How do I turn on noise suppression in Slack huddles?
Click your profile picture, choose Preferences, then Audio & video. Noise suppression is one of the microphone options there, next to automatic gain control.
Q.02Does Slack have push to talk?
In the mobile app, yes: in a huddle, open the three-dots menu to pick a speaker or turn on push-to-talk. Slack's help does not describe push to talk on desktop.
Q.03Why does my huddle sound choppy?
In a huddle with many people, Slack suggests turning off your video or noise suppression. Also check that the right mic and speaker are selected and that Slack is up to date.
§ Sources