As others have said, it’s just a horribly mastered track, which is such as shame, since she has such a great voice. I hope it’s just the mastering and not the recording, because one day, when the “loudness wars” fad is over, they’ll be able to fish out the original tapes and produce a better-sounding version of the album.
I didn’t hear any distortion on the CD, but I can hear the sound quality get a little worse from about 3:52 onwards as her voice gets louder, along with the backup vocals and instruments. If you look at this wave form, which isn’t good looking to begin with, it gets more “saturated” around 3:50, and the sound suffers.
On the other hand, when she sings the chorus earlier in the song, around 3:02, you can see there’s a little more dynamics, and it doesn’t sound as congested.
