Drop-Down Menus Stop Responding. Help!

[Moxie]

After a period of time, sometimes seconds and sometimes hours, the drop-down menus stop responding. I don't mean the right-click ones on unit frames, I'm referring to the ones in, say, the interface options window/LFG/etc.

Bugsack doesn't capture anything relevant, that I can see. I've tried disabling all addons and enabling them one by one, but the menus chose not to bork up and so I couldn't figure out what was causing it. My only other option is to enable one addon at a time and play like that for possibly hours until the menus stop responding.

I'm hoping someone here has had the same issue and can say "Aha! It was this mod! Or this conflict!", or at least tell me how I can go about figuring out which mod it is in a way that won't drive me nuts.