First test with headphones/earbuds if you can. If it still sounds fuzzy then, try testing it in another means of playing a CD (standard CD player, another computer, ect). If it still does it after that point, the CD may be messed-up (which some do degrade since certain brands use biodegradable materials for the CD's).
If it works with the headphones, then the speakers might be going bad. If it doesn't work with the headphones, but works in a different player, then it could very well be the CD drive you're using needs the lens to be cleaned or replaced.