One old diagnostic trick is to press the blade or point of a long screwdriver against the body of the AC compressor and press your ear against the handle. You actually want to make sure your ear canal is 'closed' so that you only hear the noise coming through the screwdriver.
Press the point of the screwdriver against (unmoving) parts of other reachable components.
Sounds a little primitive, but it only takes a minute, it's free, and you're likely to find the whining part that way. Of course, be careful where you point that screwdriver.
Just don't post any messages that you hear voices in the engine, or your Jeep told you to do something, or anything really nuts like that . . .