I too am having this problem. Anyone have an idea on how to fix this? Or how to set up FCP correctly so as to avoid it? I am new to FCP but have followed the Help and Manual carefully. But to no avail. Since I get the display (with a frozen frame, which updated every time playback is paused), I think I have the secondary display connected correctly. I am careful to use cmd-f12 or the menu item "all frames" (tried both over and over), but the behavior doesn't change. The canvas shows exactly the same behavior (frozen frame) as the secondary display. The canvas resumes, playing correctly, as soon as cmd-f12 is pressed or "all frames" is unchecked. Problem appears exactly the same regardless of which Cinema Desktop option is used (Main, Raw, etc.).
Help, instruction, or at least a pointer in the right direction would be very much appreciated.
Thanks,
Larry