I have a 2008 Macbook, the black one with a 250 GB hard drive and 4 GB RAM. Everything has been great with my macbook up until this week or last, the audio that comes from itunes, websites, notices, it's all scratchy. I thought it was only the built-in speakers at first but even with headphones plugged it the audio is terrible sounding. This isn't a huge problem, but I do want to make my Macbook last as long as possible. It's still got a few years left in it! Is there any troubleshooting I can try or should I schedule a repair? I'm still covered under the Apple warranty.