Photoshop: Minimize buttons disappear under upper menu bar

In CS6 my minimize buttons sometimes move under the upper menu bar. If they go too far under, I can't get them back. I've tried pressing F, but that does not make them reappear. I've tried checking/unchecking the various interface options under "preferences" and also uninstalling and reinstalling the app. So far, the only way I can fix the problem is to reset all of the defaults. I've noticed this only happens on my Mac using Mt Lion and/or Yosemite. I have another Mac using snow leopard, but on that machine it's not possible for the minimize buttons to go under the upper menu bar.