iPod cassette adapter in '91 buick stock cassette player makes screeching noise?

[Leopard Gecko 2.0]

I had purchased a cassette adapter last night, and when I hook it up to my iPod to play in the car, it makes a very annoying screeching noise that cannot be drowned out by turning the music up really loud.

Is there something wrong with the cassette player? Can it be fixed? Or is the cassette player somehow too old to be able to read the deck?