Audience has a quick look at summit (4)
I believe the answer is:
peak
'summit' is the definition.
(mountain peak)
'audience has a quick look' is the wordplay.
'audience has' indicates a 'sounds like' (homophone) clue.
'a quick look' becomes 'peek' (I've seen this before).
'peek' is a homophone of 'PEAK'.
'at' is the link.
(Other definitions for peak that I've seen before include "Sharp pointed summit" , "Pinnacle" , "Pointed mountain" , "Part of cap; mountain" , "High point" .)