Instrument at home opening red wine (8)
I believe the answer is:
clarinet
'instrument' is the definition.
(clarinet is a kind of instrument)
'home opening red wine' is the wordplay.
'home' becomes 'in' ('he's home' can mean 'he's in').
'opening' indicates putting letters inside (some letters open a gap in others).
'red wine' becomes 'claret' (claret is a kind of red wine).
'in' placed inside 'claret' is 'CLARINET'.
'at' is the link.
(Other definitions for clarinet that I've seen before include "Music-maker" , "musician" , "Single-reed straight-tubed instrument" , "Single reed woodwind instrument" , "23 instrument" .)