Audio feedback of a sort (4)

I believe the answer is:
echo
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">audio feedback of a sort</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for echo that I've seen before include "Close imitation" , "Repeated sound" , "Trace call" , "Nymph; E (radio comms.)" , "call back" .)