575 Center Console Noise

After approx 10 min of driving, a slightly loud, electrical sounding noise is coming from behind the switch panel and air vents. It sounds very much like an electrical transformer and will stay on even after all the A/C, heater and blower switches are off. When I turn the engine off, the noise is still present. Is there a solonoid or electrical component culprit at work here and how hard is that to access? Thank you.