Freezing, crackling sound from speakers, even with headphones?

I have a Windows XP, got in 2007, I don't know if that helps at all. Anyway, the sound suddenly started failing. Whenever you play sound it freezes, begins to crackle, plays slower, and/or distorts the sound. Is this a virus? It occurs even when I use the headphones. Can it be fixed? Please help me, give me any instructions to fix it. Thanks in advance.