Hello! I have Audi A6 C7, 3.0BtDi from 1 month. I like the car a lot but there is one strange noise that bothers me. So.. when engine is cold - no noise, but when it reaches 90 degrees and i drive more thna 20-30 minutes it start making some noise when i accelerate from 1200 - 1400rpm. It bothers me a lot and i would know if someone can help me. I will attach a video too. ( on video i'm already on high kms and i just press the pedal between 1200 rpm and 1400 rpm ) . Thank you!

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