public function audio() {
		if ( isset($this->custom['audio']) ) {
			return $this->custom['audio'];
		}
		$audio = false;

		// Only get audio from the content if a playlist isn't present.
		if ( false === strpos($this->get_content(), 'wp-playlist-script') ) {
			$audio = get_media_embedded_in_content($this->get_content(), array('audio'));
		}

		return $audio;
	}