To make video and audio work when a Keynote deck moves to another Mac, check three things: the media format, whether each file is included in the presentation, and its playback settings. Then test the deck on the Mac and in the playback mode you plan to use. This guide is for people preparing a Mac Keynote presentation to share or hand off.

Make sure the media can travel with the deck

Keynote supports media formats that QuickTime supports on your Mac. If a video or audio file will not insert or play, Apple recommends converting it with iMovie, QuickTime Player, or Compressor to a QuickTime video file (.mov) or MPEG-4 audio file (.m4a). The filename extension alone does not guarantee compatibility; the file must use a supported format. Apple’s instructions for adding video and audio

For a presentation that will be opened on another computer, go to Keynote > Settings > General and select Copy audio and movies into document. Apple says this ensures the soundtrack is available when the presentation is played elsewhere. Use this setting as part of your handoff check for media in the deck. A web video is different: it requires an internet connection at playback, so an embedded local movie is a better choice when the presentation must work offline. Apple’s media instructions

If the deck will be opened on older devices, check Keynote > Settings > General > Adding Media. Keynote keeps media in its original format by default; Apple documents options that convert certain formats such as HEVC or ProRes for compatibility. These settings apply to media added after you change them, not media already in existing presentations. For an existing deck, use File > Reduce File Size and consider Most compatible (H.264); choose Reduce a Copy to preserve the original. H.264 is broadly compatible, while HEVC support depends on the receiving device and operating system. Apple’s format guidance Apple’s file-size options

Set the playback behavior on each slide

Select the video or audio object, then open the Format sidebar and its Movie or Audio tab. For playback on click, leave Start movie on click or Start audio on click selected. To start automatically when the slide appears, deselect that checkbox. This setting controls when an individual media object starts; it does not make the whole slideshow start automatically. Apple’s editing instructions

For continuous media across consecutive slides, select Play movie across slides or Play audio across slides. If playback should stop at the next slide, turn that option off. To repeat media on a slide until you advance, choose Loop under Repeat. Use these controls only when that behavior is intended: an accidental autoplay setting can make a clip begin before you are ready, while click-to-play requires the presenter to start it. Apple’s editing instructions

A presentation soundtrack is configured separately in the Document sidebar’s Audio tab. Apple notes that it starts with the presentation and also plays on slides that already contain audio or video. If the soundtrack unexpectedly overlaps clip audio, check that setting and the individual media objects’ volume controls. DRM-protected music cannot be added as a soundtrack, and some downloaded media may only play on the device where it was obtained. Apple’s media instructions Apple’s editing instructions

Run a practical handoff check

Use this sequence before sending or presenting the deck:

  1. On the Mac where you prepare it, play every slide containing media. Confirm that click-to-play or autoplay matches the intended cue, and listen for overlap or unexpected silence.
  2. Save the presentation after checking Copy audio and movies into document. If you changed format optimization settings, remember they do not retroactively convert existing media.
  3. Open the saved deck on the receiving Mac if available. Test the actual file being handed off, with the recipient’s internet access if the deck uses web video. Confirm both picture and sound; a web video cannot play offline.
  4. If a local clip still fails, verify that it plays in QuickTime Player on that Mac. If it does not, convert it to a compatible format, replace it in Keynote, and repeat the playback check. If the presentation will also be used on older devices, consider making a reduced copy with H.264 and test that copy.

This sequence is a practical inference from Apple’s documented media, compatibility, and playback controls: it checks the failure points that change when a deck moves between computers. Keynote’s documented media controls do not guarantee playback in every receiving environment; web video still depends on internet access, and device support can vary by format. For a handoff, keep a copy of the deck and verify the version you actually send. Apple’s add-media guidance Apple’s format guidance

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