This is in multiplayer in an area where i do have permission to build.

What I expected to happen was that a block to be placed and the block placing sound to be played.

*What actually happened was that no sound was played, and the block wasnt placed.

All times it has happened to me i was placing cobblestone while flying close to the ground in creative.
It happens randomly, and placing blocks will work for awhile, then this starts happening.

*EDIT: this time i was flying near an extreme hill, and it happened about 10 times with a lever and twice with obsidian block.