Man has ringing in the ears leaving pub (5)
I believe the answer is:
titus
'man' is the definition.
'ringing in the ears leaving pub' is the wordplay.
'ringing in the ears' becomes 'tinnitus' (I've seen this before).
'leaving' is a deletion indicator.
'pub' becomes 'inn' (an inn is a type of pub).
'tinnitus' with 'inn' removed is 'TITUS'.
'has' is the link.
(Other definitions for titus that I've seen before include ". . . . . Andronicus, Shakespearean tragedy" , "Roman emperor from AD79" , "Roman emperor with arch" , "Groan, say" , "& 20 Mervyn Peake character" .)