# Microphone controls

Capture audio, mute sending and select an input device.

## Import and access

```tsx
import { useLocalParticipant, useLocalMedia } from '@relayrtc/react'

const local = useLocalParticipant()
const { microphone } = useLocalMedia()
```

## Requirements

A connected room, `audio:publish` permission and microphone access.

## Methods

| Method | Returns | Purpose |
| --- | --- | --- |
| enable(constraints?) | `Promise<MediaStreamTrack>` | Capture and publish microphone audio. |
| disable() | `Promise<void>` | Release capture and remove publication. |
| switchDevice(deviceId) | `Promise<MediaStreamTrack or null>` | Replace the active input device. |
| mute() | void | Pause outgoing audio while retaining capture. |
| unmute() | void | Resume outgoing audio. |
| subscribe(listener) | `() => void` | Observe the microphone snapshot. |

## Audio constraints

With no argument, enable uses an empty constraint object and lets the browser choose capture settings.

| Setting | Example | Meaning |
| --- | --- | --- |
| deviceId | `{ exact: selectedDeviceId }` | Select the input device. |
| echoCancellation | true | Request acoustic echo cancellation. |
| noiseSuppression | true | Request background noise suppression. |
| autoGainControl | true | Request automatic input gain. |
| channelCount | 1 | Request a channel count. |
| sampleRate | 48000 | Request sample rate when supported. |

Browser and hardware support determine the actual capture settings.

## Example

```tsx
await local?.microphone.enable({
  echoCancellation: true,
  noiseSuppression: true,
  autoGainControl: true,
})

local?.microphone.mute()
local?.microphone.unmute()
await local?.microphone.disable()
```

## Snapshot

Microphone uses the same [input snapshot fields](/reference/sdk/client/react/media/camera#snapshot), with `source: 'microphone'`.

Mute retains device access and is not a remote participant status message. If your UI shows remote microphone status, define a metadata field for that application state and update it along with the control.