Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 901)

Operation problems
Settings change when I switch from still photo shooting to movie
recording or vice versa.
Separate settings are retained for use when shooting still photos and recording movies.
Settings cannot be changed with < >, < >, < >, < >, or < >.
Set the power switch to < > ( ).
Check the [ 6 : Multi function lock ] setting ( ).
Settings cannot be changed with < >, < >, or < > for vertical
shooting.
Set the vertical-grip On/Off switch to < > ( ).
Set [ 7 : Smart controller ] to [ Enable ] ( ).
Touch operation is not possible.
Make sure [ : Touch control ] is set to [ Standard ] or [ Sensitive ] ( ).
A camera button or dial does not work as expected.
Check the [ 6 : Custom Controls ] setting ( ).
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