Boyfriend to play fiddle noisily (4)
I believe the answer is:
beau
'boyfriend' is the definition.
(synonyms)
'play fiddle noisily' is the wordplay.
'play fiddle' becomes 'bow'.
'noisily' shows a homophone (sound like).
'bow' sounds like 'BEAU'.
'to' acts as a link.
(Other definitions for beau that I've seen before include "Dandy - lover" , "Admirer; fop, dandy" , "young man" , "Dandy - boyfriend" , "Fop; lover" .)