Amazon.com Help: Cast Music using Alexa-enabled Devices

If the Alexa-enabled device is a third-party speaker (for example: Sonos, Bose), make sure that the appropriate Alexa skill is enabled from the Alexa companion app. iOS. To start casting from the Home Screen: Tap the Menu icon in the upper right corner. Tap Connect to a Device. Select the device to which you would like to cast your music.

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