Ripheart

So I bought this CDP 200r almost 9 years ago. It works perfectly fine, but someone dropped something on the screen and its cracked. However, it still works the way it should, except the display is half not working. However, whenever I hold the A3 note, it makes all notes from F3 to B3 ridiculously louder. When I hold the F4 key. it makes F#4 much louder. Does anyone why this is, and how to fix it?