I honestly don't think it's the supercharger itself. It is the design of the SC clutch. When the clutch engages, there is a split second of slip that occurs. This momentary slip between two pieces of steel being engaged causes the high pitched sound you're hearing. I guess it can be compared to the squeal that metallic brake pads cause on the rotor. I honestly believe the clutch would have to be redesigned to eliminate this annoyance; many people experience this issue with these engines. I've read of people replacing the SC clutch or entire SC to remedy this, but it is just a waste of time and money as far as I'm concerned. Once the clutch wears in, I guarantee the sound will return.