REAR DISK BRAKES HUMMING

Warped rotors will cause a pulsation. (50 years in the business) Rusty is correct, these rotors need to be turned (fine feed rate on the rotor lathe) and a non directional finish added.
I dont feel a pulsation. No mater how hard or soft i press the pedal If im going to take them off i just might as well get them turned