Tooltips have stopped working

[Gandite]

So normally when I inspect someone or loot a kill I can hover over an object with my mouse and a tooltip pops up telling me what said item is. After last night this has ceased to be. Oddly enough when I tell others about this they tell me its working fine for them.

Truthfully it isn't a huge, huge deal but it is rather annoying especially when I'm doing quests or trying to do something quickly. Any ideas?