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New AllCast for Fire TV headset feature

Will be released soon.

How this works:

The Allcast Fire TV app downloads the video and streams only the audio to the phone, while muting the TV.

Advanced a/v parsing is not possible on Chromecast. There's janky solutions that mimic it in other apps, by simultaneously download the video to both the phone and the TV and phone. Not ideal, and has a/v sync issues.