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# requestBeginTransmitting(channelUUID:)

Begins an audio transmission with the channel identifer you specify.

```
func requestBeginTransmitting(channelUUID: UUID)
```

## Parameters

`channelUUID`

The channel identifier.

## Discussion

Your app can only begin a transmission when in the foreground, or following a <doc://com.apple.documentation/documentation/CoreBluetooth> event, such as when a wireless accessory button triggers a <doc://com.apple.documentation/documentation/CoreBluetooth> characteristic change. The user may also begin a transmission by using the Push to Talk system user interface.

If successful, you receive a callback from [`channelManager(_:channelUUID:didBeginTransmittingFrom:)`](/documentation/PushToTalk/PTChannelManagerDelegate/channelManager(_:channelUUID:didBeginTransmittingFrom:)) with `PTChannelTransmitRequestSource.programmaticRequest`; otherwise, you receive a failure reason through [`channelManager(_:failedToBeginTransmittingInChannel:error:)`](/documentation/PushToTalk/PTChannelManagerDelegate/channelManager(_:failedToBeginTransmittingInChannel:error:)).

---

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