Present soldier with loud shirt (4)
I believe the answer is:
gift
'present' is the definition.
(I know that present can be written as gift)
'soldier with loud shirt' is the wordplay.
'soldier' becomes 'gi' (term for US soldier).
'with' is a charade indicator (letters next to each other).
'loud' becomes 'f' (short for forte - 'loud' in music).
'shirt' becomes 't' (as in a T-shirt).
'gi'+'f'+'t'='GIFT'
(Other definitions for gift that I've seen before include "''Never look a .... horse in the mouth" , "A natural attribute" , "flair" , "Offering" , "Special aptitude - present" .)