Beacon Interface Greyed Out

The beacon interface is greyed out. I was playing on a server running the 14w02c snapshot, hosted by MCProHosting. Server is 43craft.mcpro.co , have whitelisted Dinnerbone

Bug does not exist in Singleplayer.

What I expected to happen was...:
The beacon interface to appear, then I would be able to choose an effect, put in my iron ingot and press the check button.

What actually happened was...:
The entire beacon interface was greyed out, I could not even select the most basic effect, and the only press able button was the exit button, however I was still able to put in an item.

Steps to Reproduce:
Place down a beacon with the stand pyramid thingy, then right click on the beacon. You will see that the entire interface except the exit button is greyed out. (NOTE: Sometimes it works fine, other times (most times) it bugs out as above. It seems to be random.)