Loud Screaching Sound while coasting but not accelerating Audi A4 wagon

Today while driving I noticed a loud screaching sound coming from under my car while coasting but not accelerating. I don’t believe its the breaks and it sounds like metal is grinding against metal, anyone have any thoughts? THANKS!!

It’s impossiblke to tell without seeing the car. It could be brakes (torque load on the axles can have suttle effects, and it can affect noises), it could be a component bearing (acceleration puts a load on the serpentine belt and can affect noises), it could be the tensioner, it’s just impossible to tell from here. It’s always a good idea to get the brakes checked for noises like this anyway.