A summer hit maybe but it brings complaint (10)
I believe the answer is:
rheumatism
'complaint' is the definition.
(rheumatism is a kind of disease)
'a summer hit maybe' is the wordplay.
'maybe' indicates anagramming the letters.
'a'+'summer'+'hit'='asummerhit'
'asummerhit' with letters rearranged gives 'RHEUMATISM'.
'but it brings' is the link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for rheumatism that I've seen before include "ailment" , "Joint affliction" , "Inflammation of the joints" .)