Canon EOS R5 C VR Creator Kit with RF 5.2mm f/2.8 Dual Fisheye Lens - Manual (Page 373)

Caution
Voice memos cannot be added to protected images.
Voice memos cannot be recorded with an external microphone.
Note
Audio quality of voice memo recording can be changed in [ : Memo audio
quality ].
To record voice memos longer than 30 sec., repeat step 3.
You can record a single voice memo during image review (immediately after
shooting) by following step 3.
Even during transfer to an FTP server, you can add a voice memo to images from
the playback screen. However, voice memos cannot be added to the image
currently being transferred.
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