Comment 1 for bug 886624

This is a greater problem in the preferences, not just the sound hardware pane. No pane (dlgpref{eq,sound,...}) is able to disable the OK button owned by dlgpreferences, or really communicate with it at all in any meaningful way.

Not that disabling an OK button doesn't have huge usability implications of its own, I'd think most HIG groups would find it high treason.