I'm having a really strange issue with my imac. It's a late 2012, has the 680mx and is fully updated. When I click, then click very close by, the second click doesn't seem to register. For example: In Safari if I miss the little x to close a tab by a tiny amount, then click the x properly, that second click doesn't register. If I don't move the mouse away I can keep clicking and it won't register at all. If I move the mouse away, click somewhere else, then click on the x it registers the click and closes. Weird. The only thing I can think of is if I migrated some of the settings over from my macbook but I really don't think I did that. I did have magicprefs installed but I got rid of that including all its preferences. Hope that make sense, very difficult to describe. Any ideas what's going on?!