At first, I was happy with the audio on my Black MacBook. I installed Boot Camp and was still happy with the audio in Mac OS X and Windows XP. Then, one day when playing audio in iTunes I heard a pop and the audio seemed suddenly lower.
Since that time, my MacBook won't chime on restart and audio is quiet in all applications (Mac OS X and Windows XP.) If I set my volume at 50 percent or lower, you can't even hear my alert sound.
I tried PRAM zaps and PMU resets. Then, I took my MacBook to a Genius at an Apple Store. They ran a hardware test with no bad results, and even booted off an external FireWire drive and had the same audio issue. They say I have to send my MacBook in for repair. Ugh.
I need the MacBook for the next two weeks, so I will have to wait until then to back it up and send it in. if anyone has any ideas on how I can fix this myself, please let me know.