Little sound that echoes just the same? (4)
I believe the answer is:
peep
This clue is a double definition.
'little sound' is the first definition.
(peep can mean a quiet sound)
'that echoes just the same?' is the second definition.
(Other definitions for peep that I've seen before include "Secret look" , "Look furtively (in both directions)" , "Look furtively (either way)" , "Look quickly" , "Chirp" .)