Hi,

Maybe you will be nice to think about this strange sound from the back of the car. Unfortunately, the service (the car is under warranty) incl country is tragic - they know nothing...

The sound can be made very easily by driving the left front wheel into a deep hole. Then the left side of the car "dives" while the right rear quarter rises. Or when the back of the car slips gently (e.g. when it's wet in the garage). It doesn't matter if the front wheels are straight or turned. The rear axle is steerable...

This is short movie with this sound. Car have 9000km 🤦‍♂️

https://youtube.com/shorts/thU4oSgEeCg?feature=share

 

Sounds are extremely difficult to diagnose. However, I will say that when my GTC (also with rear steering) sits for a few days, there is a significantly loud "metallic" sound from the rear wheel steering the first time I turn the front wheels. But it goes away after initial use. I'd start by looking there.