What is the cause of the rattling noise in my Audi A5's engine?

I recently noticed a rattling noise coming from my Audi A5's engine. It seems to be coming from the top of the engine and can be heard when accelerating. What could be causing this sound and is it something I should be worried about? I am planning on taking my car to the dealership for regular maintenance and want to be prepared in case this is a serious issue.

The most common cause for a rattling noise in Audi A5 engines is a faulty camshaft tensioner. This can cause serious damage if left unchecked, so it's best to address it with your dealership as soon as possible. However, it could also be a loose bolt or a worn belt. Either way, it's best to have a professional take a look and diagnose the issue.