I have an '06 S I've owned 6 months. It has a beautiful sounding Milltek exhaust system but otherwise quit engine. It was the first subfreezing day last week when I jumped in and started it and I immediately noticed a new sound - a fairly loud scratchy, dry pulley sound coming from under the hood. I let it warm up before taking off and the sound nearly went away after a few minutes of driving but I just wondered if this is a tell tale sign of anything or do these cars run a little noisy when it's real cold? 112,000 on car. The supercharger oil has not been replaced but has made no sound other than the spooling wine. Any thoughts?