A place to hide sound money (5)
I believe the answer is:
cache
'a place to hide' is the definition.
I can't judge whether this definition defines the answer.
'sound money' is the wordplay.
'sound' indicates a 'sounds like' (homophone) clue.
'money' becomes 'cash' (cash is a type of money).
'cash' is a homophone of 'CACHE'.
Can you help me to learn more?
(Other definitions for cache that I've seen before include "Concealed store" , "Hiding place for treasure etc" , "Hidden store of things" , "Secret store of valuables" , "Secretly keep" .)