UPDATE: I listened for the noise again after work and isolated to somewhere behing the instrument panel. Here is something else I discovered today, when i went to turn the key to start the car I noticed that when the key got to the step just before starting the engine (when all the warning lights and instruments panel lights up) and the noise can on then without the engine being on. I tried this a couple of times and same thing happened, the noise came on before the engine was turned on. Could this be something with the electrical system?

 

I know this is an old thread, but for posterity if someone else finds it, this sounds like it may be a HVAC blend actuator that is going bad.