Sounds play twice when opening inventory.

If you break or place a block/item and at the time the block/item breaking/placing sound plays open your inventory the same sound will play when you close your inventory a couple of seconds later. I found it easier to reproduce in creative, just click and press E almost instantaneously and when you press E again you will hear the same breaking/placing sound. This also occurs in survival but it is harder to get the timing right.