Hi,
Did you restart FCPX?
FCPX will only pick up the single output option specified in the Blackmagic preferences. For example, if you set 1080p 23.98 in the Blackmagic preferences and start FCPX, the only option you’ll see is 1080p 23.98. This is regardless of what your timeline format is as FCPX will convert the output on the fly to match your required output.
Say you want to change the output format to 1080i50, then you’ll need to do so in the system preferences and then restart FCPX for it to pick up the new format.
I hope this makes sense.
regards
Kristian Lam
Blackmagic Design