I wanted to mute fire, so I turned off "Blocks" 's volume setting. That didn't work, so I tried "Ambient/Enviroment". That didn't work either. Then I muted every volume category other than "Music" and "Master Volume", and I could STILL hear the fire. The only way to mute the fire is to turn off the "Master Volume." That is lame, because then Minecraft has no sound whatsoever. I want to be able to mute fire without having to mute all Minecraft sounds.
I was unable to reproduce this, Fire would make no sounds when I turned off the Blocks volume.