Why is my Audi A6 engine making a rattling noise?

I've noticed that my Audi A6's engine has been making a rattling noise while idling. What could be causing this and how can I fix it?

One possible cause could be a loose or damaged component in the engine, such as the pulley or belt. It's important to get this checked and repaired as soon as possible to prevent further damage.

Another potential cause could be low engine oil levels or degraded oil. Check your oil levels and quality and if necessary, get an oil change to see if this resolves the issue.

It's also possible that the rattling noise is coming from the exhaust system. Make sure all the bolts and brackets are securely fastened and consider getting a professional inspection to identify any potential problems.