Member of audience is unusually silent before the Queen (8)
I believe the answer is:
listener
'member of audience' is the definition.
(I've seen this before)
'unusually silent before the queen' is the wordplay.
'unusually' is an anagram indicator.
'before' is a charade indicator (letters next to each other).
'the queen' becomes 'er' (Elizabeth Regina**).
'silent' is an anagram of 'listen'.
'listen'+'er'='LISTENER'
'is' is the link.
(Other definitions for listener that I've seen before include "One enjoying radio broadcast" , "One lending an ear" , "Difficult Times Saturday crossword" , "Radio fan" , "One giving attention" .)