Uproar caused by 150, having a love affair (7)
I believe the answer is:
clamour
'uproar' is the definition.
(I've seen this before)
'150 having a love affair' is the wordplay.
'150' becomes 'CL' (Roman numerals).
'having' is a charade indicator (letters next to each other).
'a love affair' becomes 'amour' (I've seen this in another clue).
'cl'+'amour'='CLAMOUR'
'caused by' is the link.
(Other definitions for clamour that I've seen before include "Loud noise of shouting" , "Hue and cry" , "Loud confused noise" , "Loud and persistent outcry" , "racket" .)