Check your setting for G4 (the movie action for shutter).

If you have that set to "take movies" then the "lock mirror up" will be greyed out.

Changing banks will reset that setting, so it magically becomes not-greyed.

My guess -- GUESS -- is that this is not a bug, but a coincidence. Someone didn't know about the G4 setting, when they changed banks it worked - presto.

See if perhaps that was your issue?

Linwood

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