Forest sound on an old record (6)
I believe the answer is:
epping
'forest' is the definition.
(I've seen this before)
'sound on an old record' is the wordplay.
'sound' becomes 'ping' (ping is a kind of sound).
'on' is a charade indicator (letters next to each other).
'an old record' becomes 'EP' (abbreviation for extended play record).
'ping' put after 'ep' is 'EPPING'.
(Other definitions for epping that I've seen before include "Essex site of a forest" , "Forest near London" , "Forest NE of London" .)