Scraping Sounds

[Noahvel]

My 2000 boxster has recently started making a faint scraping sound. It sounds like it is coming from the back of the car. It is very faint and only happens when I am making sharp turns or accelerating. It sounds like metal dragging on the road but there is nothing hanging down. I don't know if it is related but sometimes when I downshift or start on a hill my car makes a very loud almost shriek sounding sound. Does anyone maybe know what these sounds are, and why they are happening?

Thanks for the help.