Thanks to Siri, the fourth-generation Apple TV has a couple of ways to easily bring up closed captioning while you’re watching a show, ranging from simply asking Siri to “turn on closed captioning” or “subtitles” to the very useful “What did he say?” query, which will automatically skip back a few seconds and temporarily turn subtitles on. While these are handy enough for many, if you find that you don’t always want to talk to Siri in the middle of a movie, you’ll be happy to know that you can also assign closed captioning to an accessibility shortcut on your Siri Remote, allowing you to toggle closed captioning on and off by simply triple-clicking the menu button.

You can find this feature in the General, Accessibility section of your Settings app — look for the Accessibility Shortcut option down at the very bottom.
In here, you’ll find a number of accessibility options that can be activated (or deactivated) whenever you triple-click the menu button, including Closed Captions. Select this option (a checkmark will appear to confirm it’s activated), and triple-clicking the menu button while watching a program will toggle the closed captions on and off without interrupting whatever you’re watching.
Note that you can assign more than one accessibility feature to the shortcut — each selected option will be indicated with a checkmark beside it; if multiple options are assigned, triple-clicking the menu button will bring up a full-screen menu asking you to select which feature you want to enable.
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