Grinding/Crunching Noise From The Engine When Stationary

[AJAY112]

Hi all,

I have an Audi A3, 2015, S-Line, 2.0 TDI, Diesel and I have recently heard a faint grinding or crunching noise coming from the engine area, like a 'Skrrr Skrrr' noise when the engine is stationary. I have taken it to Audi several times and they are unable to rectify the fault. I am concerned that it could lead to something major and cost me a pretty penny in the future. I have attached a video for the sound to be heard hopefully over the loud diesel engine. If anyone would be kind enough to identify the noise or fault, it would be highly appreciated. 

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