Fiddled around, capturing electronic piece of music (7)
I believe the answer is:
rondeau
'piece of music' is the definition.
'fiddled around capturing electronic' is the wordplay.
'fiddled' indicates an anagram.
'capturing' is an insertion indicator.
'electronic' becomes 'e' (as in e-mail or e-books).
'around' anagrammed gives 'rondau'.
'rondau' going around 'e' is 'RONDEAU'.
(Other definitions for rondeau that I've seen before include "Poem of ten or thirteen lines" , "Short poem with only two rhymes and opening words used twice as refrain" , "Sort of poem" , "set of lines" , "Style of poem" .)