Why is my Audi's engine making a humming noise?

I recently noticed that my Audi's engine is making a strange humming noise. What could be causing this and what should I do about it?

It is possible that the noise is coming from a faulty exhaust system. I would recommend getting it checked by a mechanic as soon as possible to avoid any potential damage to your engine.

Another possible cause could be a problem with the bearings in your engine. I would suggest taking it to a certified Audi dealership for a thorough inspection.