Forge 1481
CB 3.3.6

Like the title says, heres a picture. Relogging into the world fixes it. Not really sure if its a big issue as a simple world reload fixes it but i thought it would be worth mentioning.

I suspect some of the tile entities aren't loading correctly when you join the world. This is an old problem that is very isolated and hard to reproduce (it's probably only client-side). Usually, even vanilla items that rely on tile entities exhibit similar behavior such as signs with disappearing text, and possibly even chests.