I think I know what you're talking about since I have the Kline as well, it's normal. Only real way to turn off is tune. If you want it real loud all the time then get the headers. It's the ecu that's programmed in all new porsche's that the valves won't truly open until higher rpm regardless if you have valve controller or not. I have soul valve controller and can confirm it does work, however it still doesn't have the true exhaust sound until later rpms around 4.5k