It has charms, we hear (5)
I believe the answer is:
music
'it has charms' is the definition.
The definition suggests a singular noun which matches the answer.
'we hear' is the wordplay.
I cannot quite see how this works, but
'we' could be 'us' and 'us' is found within the answer.
The remaining letters 'mic' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for music that I've seen before include "'''If ... be the food of love, play on'' (Twelfth Night) (5)'" , "Pleasant sound (to one's ears)" , "Sweet sound." , "Airs" , "Composed sound" .)