Why is my Audi A5 making a rattling noise while idling?

I have recently noticed a rattling noise coming from my Audi A5 while it is idling in park. It seems to go away once I start driving, but comes back when I am at a stop again. What could be causing this and how can I fix it?

The issue is likely with the engine mounts. They can wear out over time and cause the engine to vibrate and create a rattling noise. I would recommend having them checked and replaced if needed.

Another possibility is that there is debris caught in the exhaust system. This can also cause rattling noises. I suggest taking your car to a mechanic to have the exhaust system inspected and cleaned.