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# setAutoGainControl

> Toggle browser automatic gain control on the local mic at runtime.

```ts
setAutoGainControl(enabled): Promise<boolean>
```

Toggle browser automatic gain control on the local mic at runtime.

## **Parameters**

**`enabled`** `boolean` — required

Whether automatic gain control should be enabled.

---

## **Returns**

`Promise<boolean>` — whether the constraint reached the microphone.

`false` is an outcome rather than an error: a leg sending media the SDK did not capture is left alone. A UI that reflects the toggle must read this value instead of assuming the call succeeded. Any failure behind a `false` is also reported on [`errors$`](/docs/browser-sdk/v4/reference/webrtc-call/errors\$).

## **Examples**

### Toggle from a UI switch

```ts
agcSwitch.addEventListener('change', async (e) => {
  await call.setAutoGainControl(e.target.checked);
});
```

## **See**

* [`setEchoCancellation`](/docs/browser-sdk/v4/reference/webrtc-call/set-echo-cancellation), [`setNoiseSuppression`](/docs/browser-sdk/v4/reference/webrtc-call/set-noise-suppression) — companion processing toggles.

> Toggle browser automatic gain control on the local mic at runtime.