> Fetch clean Markdown by appending `.md` to any page URL under https://signalwire.com/docs or requesting it with the HTTP header `Accept: text/markdown`. The root index at https://signalwire.com/docs/llms.txt lists the available documentation indexes.

# addDevice

> addDevice method for the RoomSession class.

### addDevice

* **addDevice**(`opts`): `Promise<RoomSessionDevice>` - See [RoomSessionDevice documentation](/docs/browser-sdk/v3/js/reference/video/room-session-device) for more details.

Adds a device to the room. Using this method, a user can stream multiple sources at the same time. If you need to add a camera device or a microphone device, you can alternatively use the more specific methods [addCamera](/docs/browser-sdk/v3/js/reference/video/room-session/add-camera) and [addMicrophone](/docs/browser-sdk/v3/js/reference/video/room-session/add-microphone).

#### Parameters

**`opts`** `object`

Specify the constraints for the device. In addition, you can add the `autoJoin` key to specify whether the device should immediately join the room or joining will be performed manually later.

---

**`audio`** `boolean | MediaTrackConstraints`

Audio constraints.

---

**`autoJoin`** `boolean`

Whether the device should automatically join the room. Default: `true`.

---

**`video`** `boolean | MediaTrackConstraints`

Video constraints.

---

#### Returns

`Promise<RoomSessionDevice>` - See [RoomSessionDevice documentation](/docs/browser-sdk/v3/js/reference/video/room-session-device) for more details.

#### Permissions

* `room.self.additional_source`

You need to specify the permissions when [creating the Video Room Token](/docs/apis/rest/video/room-tokens/create-room-token) on the server side.

#### Example

Adding any of the microphone devices to the room (duplicate streams are possible):

```javascript
await roomSession.addDevice({ audio: true });
```

> addDevice method for the RoomSession class.