Rot about doctor is not confusing musician (10)
I believe the answer is:
trombonist
'musician' is the definition.
(I know that trombonist is a type of musician)
'rot about doctor is not confusing' is the wordplay.
'about' indicates anagramming the letters.
'doctor' becomes 'mb' (Bachelor of Medicine, Medicinae Baccalaureus).
'confusing' indicates anagramming the letters.
'rot' is an anagram of 'tro'.
'is'+'not'='isnot'
'isnot' anagrammed gives 'onist'.
'tro'+'mb'+'onist'='TROMBONIST'
(Other definitions for trombonist that I've seen before include "Ted Heath, perhaps" , "Brass player" .)