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filter is not described

wp_audio_extensions filter-hook . WP 3.6.0

Filters the list of supported audio formats.

Usage

add_filter( 'wp_audio_extensions', 'filter_function_name_1627' );
function filter_function_name_1627( $extensions ){
	// filter...

	return $extensions;
}
$extensions(array)
An array of support audio formats.
Default: are 'mp3', 'ogg', 'flac', 'm4a', 'wav'

Where the hook is called

wp_get_audio_extensions()
wp-includes/media.php 2162
return apply_filters( 'wp_audio_extensions', array( 'mp3', 'ogg', 'flac', 'm4a', 'wav' ) );

Where the hook is used (in WP core)

Does not used.