Description:
When joining a server there is a possible chance to become invisible to everyone. While invisible some sound effects will not work. For example; burning in lava, falling off something and more. While in this state you can take damage but it doesn't appear you are when people hit you since they can't see you nor hear you. When testing with someone who was invisible, when trying to set there scoreboard value to something it wouldn't work. The player who is invisible wouldn't appear to be to themselves. The only way we have found to get out of this state is to disconnect from the sever and connect back. We have tested this on various of different servers and all the 1.9 snapshots.

Steps to replicate:
1. Create a server with the newest snapshot.
2. Get some people to join it.
3. Join and leave until they see you invisible.
4. After a couple tries you should have got it by now.