Audio tag does not seem to be supported

Gutenberg generates

<!-- wp:audio {"id":123} -->
<figure class="wp-block-audio"><audio controls src="https://my.domain.com/wp-content/uploads/2020/06/my-soundfile.mp3"></audio></figure>
<!-- /wp:audio -->

When I run the scan, all mp3 files are listed as “unused”.

Adding

		// Audios: src
		$audios = $dom->getElementsByTagName( 'audio' );
		foreach ( $audios as $audio ) {
			//error_log($audio->getAttribute('src'));
			$src = $this->clean_url( $audio->getAttribute('src') );
    	array_push( $results, $src );
		}

to core.php below the $videos hander works for my, but maybe I miss things…