Sort out drink for public platform (7)
I believe the answer is:
rostrum
'public platform' is the definition.
(I've seen this before)
'sort out drink' is the wordplay.
'out' is an anagram indicator (out can mean wrong or inaccurate).
'drink' becomes 'rum' (rum is a kind of drink).
'sort' is an anagram of 'rost'.
'rost'+'rum'='ROSTRUM'
'for' acts as a link.
(Other definitions for rostrum that I've seen before include "Platform for speaker" , "Platform for orchestra conductor" , "Conductor's dais" , "Raised platform" , "beak" .)