Damp down the Mounties every so often (4)
I believe the answer is:
mute
'damp down' is the definition.
'mute' can be an answer for 'damp' (synonyms). I am not certain of the 'down' bit.
'mounties every so often' is the wordplay.
'every so often' means one should take alternating letters.
The alternating letters of 'mounties' are 'MUTE'.
'the' acts as a link.
Can you help me to learn more?
(Other definitions for mute that I've seen before include "Device for softening musical sound" , "Violin clamp; type of swan" , "Silent - dumb" , "Silence" , "Silent, not talking" .)