2003 jap import sti

Imported 3 months ago, air con never was cold. But it was noisy, not sure if its the compressor or the clutch. its my understanding that the compressor should'nt be turning when the air con is off meaning that if it is making noise all the time then it would be the clutch mechanism ?

Their is no difference in sound when the turn the air con on/off, or no difference in sound if I am listing in front of the air con unit itself either when on/off

Would this be right that its the air con clutch ?