Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 430)

Voice Memo Recording and Playback
Recording Voice Memos
Playing Voice Memos
You can add (record) voice memos to your shots. Voice memos are recorded as WAV audio
files with the same file number as the image. They can be played back by the camera or a
computer.
Recording Voice Memos
1.
Switch to playback.
2.
Select an image to add a voice memo to.
Turn the < > dial to select an image to add a voice memo to.
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