Audience member lies rent apart (8)
I believe the answer is:
listener
'audience member' is the definition.
(I've seen this before)
'lies rent apart' is the wordplay.
'apart' indicates anagramming the letters.
'lies'+'rent'='liesrent'
'liesrent' is an anagram of 'LISTENER'.
(Other definitions for listener that I've seen before include "One giving attention" , "Eavesdropper" , "Dead body" , "One following advice" , "Former BBC magazine" .)