Why is my Audi A6's engine making a high-pitched whining noise?

I recently noticed that my Audi A6's engine has been making a loud, high-pitched whining noise when I accelerate. This noise seems to be coming from the front of the car, near the engine. What could be causing this and how can I fix it?

The most likely cause of this noise is a worn or loose serpentine belt. It's important to get this fixed as soon as possible, as a damaged belt can cause other engine components to fail. I recommend bringing your car to a trusted mechanic to have the belt inspected and replaced if necessary.

Another possible cause could be a problem with the alternator. It's responsible for providing power to your car's electrical system, so if it's malfunctioning, it can cause strange noises like the one you described. I suggest taking your car to a dealership to have them diagnose and fix the issue.

It's also possible that the noise is coming from a faulty pulley or tensioner. These components help keep the serpentine belt in place and tensioned, so if one of them is damaged, it can cause the belt to slip and make noise. I recommend taking your car to a certified mechanic for a thorough inspection and repair.