Why is my Audi A5 making a strange sound when I accelerate?

I've noticed that my Audi A5 started making a strange sound when I accelerate. It's a low rumbling noise that seems to be coming from the front of the car. What could be causing this and how can I fix it?

It's possible that the sound is coming from a faulty exhaust system, such as a loose or damaged muffler or an exhaust leak.

Another possible cause is a worn or damaged belt in the engine, which can create a whining or squealing noise when accelerating.

If the sound is more of a clicking or tapping noise, it could be a sign of an issue with the valve train or valve lifters.