Whining noise at highway speeds. Any Idea?

I have been getting a whining noie from my completely stock 02 WRX with about 54k on it. It usually happens after being on the highway for about 20 minutes. There will be a whining noise coming from the front half of the car somewhere. It does not change through shifting gears, depressing the clutch or varying speed. It will make the high pitch noise for a time and then stop.

This has been happening for a while and a recent change gear lube did not change the situation. Does anyone think it could be the AC cycling? I haven't tested that idea yet. I alsoo read something about a pin in the front differential that can get sheared off and cause something like this.

Any ideas?

 

it sounds like its your belt..

 

could be the AC belt if your running defrost all the time, but that should change pitch w/ engine speed.

it could be the rear view mirrors, i know people have problem w/ those whistling at higher speeds. (ie 100+) but the older the car gets the more they whistle. mine do it @ about 80 but my car is 10yrs old.