If you open inventory right after placing or removing a block (while the sound was still playing), it will be replayed once you close the inventory.
Works both in Survival and Creative.
What I expected to happen was...:
I expected no sound to be played after closing inventory.
What actually happened was...:
A sound is played of the last action (placing/removing block) after closing inventory window.
Steps to Reproduce:
1. Place or remove a block and immediately open inventory
2. Close inventory and listen
Related issues
Comments

Confirmed. The inventory must be closed somewhat quickly.
Confirmed with opening and closing chests as well.
It's still there, though MC-35714 reports being fixed for 1.7.1. Block breaking/placing and chest opening sound still replays after closing inventory window. Jukebox I do think is fixed (at least I can't replicate it).
This happens if you press the inventory key the moment any sound is played. I can confirm it in 1.7.2 with OpenJDK on Linux.
this extends to other sounds as well. I noticed it when opening and closing my inventory next to a empty dispenser hooked up to a clock. the clock usually was at regular intervals near a second but when opening my inventory it had an extra tick.
This Bug is still present in the Snapshot released today (14_08a).
I uploaded a short clip (15 seconds) demoing the bug. https://dl.dropboxusercontent.com/u/5711047/Sound%20Bug%20in%20Minecraft%201.8.wmv
Confirmed in 1.8.8
NOTE - This also happens when closing the chat box
Confirmed. You can hear block breaking sounds a second time right after closing the inventory when the inventory was opend directly after destroying a block.