Taking issue about press operator (7)
I believe the answer is:
surgeon
'press operator' is the definition.
'surgeon' can be an answer for 'operator' (someone who operates). I'm not sure about the 'press' bit.
'taking issue about' is the wordplay.
'taking issue' becomes 'surge' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'about' becomes 'on' (as in a book 'on' a certain topic).
'surge'+'on'='SURGEON'
(Other definitions for surgeon that I've seen before include "Theatre operator" , "9 practitioner (through keyhole?)" , "Doctor with a scalpel" , "incisive person" , "Hospital worker" .)