The choir's content to bounce off walls (4)
I believe the answer is:
echo
'bounce off walls' is the definition.
'echo' can be an answer for 'bounce' (I've seen this in another clue). I am not certain of the 'off walls' bit.
'the choir's content' is the wordplay.
'content' says the answer is hidden in the clue (letters contained within the clue).
'ECHO' can be found hidden inside 'the choirs'.
'to' is the link.
Can you help me to learn more?
(Other definitions for echo that I've seen before include "Trace call" , "Sound bouncing back" , "one catches on the rebound?" , "Ape" , "Reflected sound" .)