I also experienced this problem. Galaxy S4
This is a feature. Tommaso wanted a little variation in forests.
I looked in my Minecraft file and all sounds are there.
More details also. In Snapshot 1.7, the sliders no longer crash the game. There are none of the sounds mentioned in the previous comment. The sound of eating, throwing eggs, and bows are also gone. Menu sounds are not present, either. No signs of music either (Ambient or Jukebox). Flowing water sound is present, though. I really want to use the pre-release, but with all these sounds missing, it drives one crazy.
I disagree with the resolution of this ticket. The issue that this one "duplicates" is speaking of a completely different sound-based issue. MC-35623 talks about sounds of placing blocks, along with other mob sounds, while this issue is speaking of walking sounds and the sounds made during the duration of time that a block is breaking. The sound of the block as it switches from a block to an entity is still there, but the sound for while you are actually applying the tool and waiting on the block to break is not there. Also, the sound of picking up a tile drop is not present. As of Snapshot 1.7 this bug is still occurring.
Can confirm, using a VPN allowed it to work for me, too.