I was flying around exploring all of the new biomes in 1.7.2 when the background music began playing a different track, This would be fine, except the track that was currently playing never stopped. This created some very uncomfortable dissonance in the sound. *What I expected to happen was....: The first track would fade out as the second track began.
*What actually happened was...: The first track never stopped playing and the 2 tracks were playing simultaneously.
Steps to Reproduce:*
1. Make sure music is on
2. Eventually the background music will play 2 songs at once.
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Apparently, Minecraft will play a song in the background even if you turn off music. The overlap was bothering me, so I turned off music, and a song still played. I'm pretty sure it even overlapped.