Back speakers

I did not get the extra hghi-end audio option, so I have been assuming that those large speaker grills are fake. After driving over one year, still I am not sure if any sound are coming from those. Does anyone know if there are speakers behind the speaker grill?

Even the base audio has two small mid-range speakers in the back. Turn the fader all the way to rear. If you can't hear something, take the car in.