Hi @Dyedhalo! Thanks for posting.
Casting is not supported on Xbox devices. There are some third-party applications available for casting from your mobile device to Xbox devices.
However, Pandora does not officially support these apps.
Keep in mind, YouTube works a little different and gives the option to stream directly on devices that are on similar networks.
Let me know if you experience the same listening issues when streaming from the Pandora app available in the app store of your device.
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