Why does my Audi A8 engine make a ticking noise?

I recently noticed that my Audi A8's engine has started making a strange ticking noise. It seems to happen when the engine is idling or at low speeds. What could be causing this and how can I fix it?

This ticking noise could be caused by a few different things, such as a problem with the timing belt or a faulty valve lifter. I recommend taking your car to a trusted mechanic to have it inspected and repaired if necessary.