Thanks for your response.
I do indeed use Winamp. I also used the EQ as well. For testing, I turned it off, however the crackling is still there on the piano notes (Where it crackles the strongest).
I spent quite a lot of money on the X-Fi XtremeMusic card back when it first came out. Why on earth would it be the sound card? Is Soundblaster just pathetic or something? If so, what brand would you guys recommend? I want a flawless sound card for my flawless headphones (Without spending $500, mind you.) I only listen to music, I don't produce it, so I don't need anything a professional would use. I just want a sound card that doesn't crackle on those piano keys.
I'm assuming here that I need to buy a new sound card. I don't want to, but if you guys tell me the X-Fi XtremeMusic sucks and could very well be the source of the problem, then I'll go get a new one. I'd still be open to other (less expensive) solutions to the problem as well.
Thanks for the continued help.