I have a 2004 Grand Prix GTP with 31,000 miles and I have noticed a high pitched whining noise that occurs during acceleration. It gets higher and louder as I accelerated and changes back to a lower, quieter noise as the transmission shifts to the next gear and progresses with each gear. I tend to notice it more during the start up phase, but it is always there to some extenet, just quieter as the car gets warmer. Do I need to be worried or is it the supercharger noise?
I have an 05 GTP and installed a K&N cold air induction kit on it for $300, which basically takes the intake out of a box and moves the intake filter to the ambient air under the hood. You can really notice the whine of the supercharger with the kit. I didn’t notice it much prior to installing the kit. If you or someone else did not install the kit, perhaps there is a leak or crack in the air filter box or hose going to the supercharger intake allowing some noise to escape. The kit claims to add 17-18 horsepower and causes some real glances when punched.
Yeah, I was going to say, I think it’s the big ol’ roots-style supercharger bolted to the top of your motor. I’d kill to have that whine in my car 
One thing that you MIGHT consider doing is looking at your owner’s manual and seeing what sort of maintenance your supercharger requires. It may require none, but likely it needs its oil replaced at some point (I may be off base, but a lot of forced induction systems have their own oil system that needs to be checked and possibly replaced at some point.)