Placing any block right next to an entity that would collide with --but does not occupy the space, will cause the block to be placed with no sound nor hand animation.

This easily reproducible by digging a 2x2x2 hole and moving iron golems inside until they start getting pushed away to the edges. 3 to 4 iron golems are enough. Afterwards, start breaking and placing down the blocks that make the edge of the hole; you should note the issue right away if the iron golems are colliding with that side of the hole.
_{(A possible setup is shown in the screenshot. The visible blocks next to the golems present this issue)}