Audio::withJsonString

public function withJsonString($json)
{
	if($json <> '')
	{
		try
		{
			$params = Json::decode($json);
			if($params['type'] == self::AUDIO_TYPE_PRESET)
			{
				$this->withPreset($params['preset']);
			}
			if($params['type'] == self::AUDIO_TYPE_FILE)
			{
				$this->withFile($params['fileId']);
			}
			if($params['duration'])
			{
				$this->duration = $params['duration'];
			}
		}
		catch(ArgumentException $e)
		{
		}
	}
	return $this;
}