Rear defrost and rear speakers dont work when its cold outside.
 

I have a 99 pontiac sunfire, and when it is cold outside, below 50 degrees or so, the rear window defrost and rear speakers stop functioning. Never has one worked and the other not, both are always out at the same time. I can park the car, leave it until its warm outside (the car is not running during this time) and all of a sudden they both work again when its warmer outside. I am getting very frustrated with this, its not a major issue at the very moment but it is going to be as I am moving to Chicago from San Diego in a week and cannot afford to take the car in to a professional shop or dealership. If anyone has any suggestions it would be greatly appreciated.
Thanks