My MCS started making a low grinding noise on the way to work at 75. Half way there I noticed it goes away or gets less at higher RPM but gets louder at lower RPM. On the way home it wasn't as bad until half way there. That's when it turned into a higher pitched grinding noise with the occasional clunking. Released the tension off the tensioner & started it up & it was quiet so it has to be either one of the pulleys or the supercharger itself. But while driving the supercharger was boosting with no problems just the grinding noise. Is there a way to figure out what's going on? Tried using the screwdriver to ear trick but was only able to do it with the tensioner bracket that's connected to supercharger & it's definitely in that general area.