Windows 8 Harddrive Hibernate

I played a game with the new Snapshot.
I stopped playing and went away to eat something.
My harddrives turn themselves off after 20 minutes.
When I came back, I pressed "Back to Game", but was stuck.
I had some other "disc-turning-off" problems with other programs.
The attachment shows the log.

What I expected to happen was:
The game should be resumed.

What actually happened was:
The game crashed because my harddrives needed too long to start again.

Steps to Reproduce:
1. Edit the turn-off time in the advanced powermanagement options.
2. Start a Minecraft game, pause it, leave the PC for the set time without any interaction.
3. Resume the game afterwards.

EDIT: I could not reproduce it yet.
Still there should not occur an ClassCastException...