VW GOLF 7 2018 MODEL

I bought a brand new Golf 7 2018 model with lots of additional features. Since the before the first service the car was making whining noise coming from the engine. Almost the sound of a windinh belt sound. Especially when driving on a incline and at a slow speed or in traffic. I have taken the car to VW Germiston , VW Constantia - both have confirmed that is nothing . Saying there are flat spots on the tyres. But flat spots on tyres don't make a whining belt noise. I suspect it is the turbo and they do not want to repair while still under warranty. and When the warranty is up then I will have to fork out the cash.Very disappointed with the After sales service of VW.