What about mine? A quiet final tribute (7)
I believe the answer is:
epitaph
'final tribute' is the definition.
(an epitaph is written for a dead person)
'what about mine? a quiet' is the wordplay.
'what' becomes 'eh' (sound used to ask 'what?' or 'pardon?').
'about' indicates putting letters inside.
'mine?' becomes 'pit' (down the pit).
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'pit'+'a'+'p'='pitap'
'eh' placed around 'pitap' is 'EPITAPH'.
(Other definitions for epitaph that I've seen before include "Memorial words" , "Grave inscription" , "last words" , "Gravestone message" , "Commemorative inscription" .)