Why does my center console get hot in my bmw 740i?

ive noticed over the last 7 days or so wen i drive for more than 15 mins my center console and steering colloum get realy hot to touch. and i mean hot... it makes the car uncumftorble to drive. the engine doesnt over heat or drive strange, oils ok fluids all ok .blowers blow both hot and cold and air con works. it gets so hot the screen in the center console starts to loose pixles of display and you can feel the heat radiating form it. if any one has came across this or has any ideas please tell as the garage cant give an answer and it is a lovely car i dont want to get rid of. if u need more info i will do my best to provide wot i can. thanx