Canon EOS-1D X Mark II DSLR Camera (Body Only) - Manual (Page 519)

519
Troubleshooting Guide
If there is a drastic change in the exposure level during autoexposure
movie shooting, the recording will stop momentarily until the
brightness stabilizes. In such a case, shoot in the <
a > mode (p.301).
Since the High Frame Rate movie will be recorded as a 29.97 fps/
25.00 fps movie file, it will play back in slow motion at 1/4 speed.
Make sure the [ 5 3: Video system ] is correctly set to [ For NTSC ] or
[ For PAL ] (depending on the video system of your TV set).
Make sure the HDMI cable’s plug is inserted all the way in (p.379).
If the movie file size reaches 4 GB, another movie file will be created
automatically (p.320). However, if you use a CF card exceeding 128
GB or a CFast card formatted with the camera, you can record a
movie to a single file even exceeding 4 GB.
You can grab frames only from 4K movies. Frame grabbing is not
possible with Full HD movies or 4K movies shot with a different
camera model.
The movie appears to freeze momentarily.
The movie plays in slow motion.
No picture on the TV set.
There are multiple movie files for a single movie shoot.
I cannot grab frames from a movie.