04 Supercharger Noise!?!?

I have a 2004 3800 Supercharged GP GTP... When I hit the gas there is a high-pitched whistling sound that sounds to me like to supercharger spooling up, but it is way louder than should be and very annoying. I have driven other GTPs and you cannot hear the sound at all. I don't know what else could be making this noise.

Has anyone had a similar experience or know what might be causing this? Is there anything I can do to fix this? I'd rather not spend $500 to have the dealer look at it!

Thanks!!!

Welcome to AF!!

There are several possibilities. First, are you having any drivability issues? I would check the following in an attempt to diagnose. First, remove the supercharger belt to see if the source is the supercharger itself. It could be something other than the supercharger, like a bad tensioner pulley that gets louder as you drive. Second, check to make sure that the supercharger has plenty of oil. If it is dry you could have a bearing issue. I doubt this is the case. Finally, check the car for a vacuum leak. You could have a small leak that is presenting itself when the engine is under load.

I hope this gives you somewhere to start. Post again if all of this checks out.