ACF repeater field causing errors in output

Hi there, I am experiencing the same issue as this closed post:

https://ww.wp.xz.cn/support/topic/acf-shortcode-variable-shows-error/

I am outputting the url of an mp3 in the media library via an ACF Pro field.

$file = get_sub_field('audio-file');
echo do_shortcode('[sc_embed_player fileurl="' . $file . '"]');

I get an error: “Compact Audio Player Error! You must enter the mp3 file URL via the “fileurl” parameter in this shortcode. Please check the documentation and correct the mistake.” and yet the audio player is displaying and playing fine in spite of the error.

If I echo $file, I get the correct path to the mp3 in question.

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