Canon EOS RP Instruction Manual page 753

C.Fn III-9: Audio compression
Sets audio compression for movie recording. [1: Disable] allows higher
audio quality than when audio is compressed, but file sizes are larger.
0: Enable
z
1: Disable
z
Editing movie files recorded with [1: Disable] and then saving them with
o
compression will also compress the audio.
Audio is compressed even if [1: Disable] is selected when [Movie rec. size]
o
is set to L6V (NTSC) or L5V (PAL).
Audio for video snapshots is compressed even when [1: Disable] is selected.
o
Custom Function Settings
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