Troublesome person with stick always set about music maker (4,5)
I believe the answer is:
reed organ
'music maker' is the definition.
(reed organ is a kind of musical instrument)
'troublesome person with stick always set about' is the wordplay.
'troublesome person' becomes 'nag' (a person who constantly troubles others).
'with' says to put letters next to each other.
'stick' becomes 'rod' (I've seen this before).
'always' becomes 'eer' (poetic way of saying ever).
'set about' says the letters should be written in reverse.
'nag'+'rod'+'eer'='nagrodeer'
'nagrodeer' back-to-front is 'REED-ORGAN'.
(Other definitions for reed organ that I've seen before include "small instrument" , "Keyboard instrument, harmonium" , "What you might hear" , "Melody Maker?" , "supports traditional services" .)