Before today, Digital Cinema Desktop Preview in Final Cut Pro had never worked on my Macbook Pro.
I finally figured it out and am posting it here so you don't have to sift through endless forums, reinstall software, etc. to no avail.
Solution:
It's just a checkbox.
Go to the Final Cut Pro menu to Audio/Video Settings:
Click the A/V Devices tab:
Check the Mirror on desktop checkbox:
That's it. It was for me anyway.
Click OK, hit CMD-F12 and you should be in business.
(Note: once in a while I'll post solutions I find to problems to save people the agony that I've suffered. I keep them to a minimum. But probably the most useful articles on here...)
