This is quite a minor thing but it kind of ruins the immersion whilst walking around, especially in the new caves with the new block sounds.

Basically, when you walk at the very edge of a block and there is no block next to it, no step sounds will play. This effects even walking down slopes - You don't get this constant feedback of sound and it is quite jarring.

The screenshot I've added shows where the player has to be when the sounds do not play. If you walk forward in that specific position, no step sounds will play.