Devise\Pages\Fields\Handlers\AudioFieldUpdated::findUnprocessedFiles PHP Method

    protected function findUnprocessedFiles($field, $settings)
    {
        $unprocessed = array();
        $duplicated = array();
        // loop through settings and see if the
        // file located at setting[label] already exists
        foreach ($settings as $setting) {
            if ($this->MediaPaths->fileExists($setting['label'])) {
                $duplicated[] = $setting;
            } else {
                $unprocessed[] = $setting;
            }
        }
        return array($unprocessed, $duplicated);
    }