Alpina B7 supercharger noise?

[MontanaRob]

I'm new to my ride and recently I now hear a momentary SCREEEEEErrrCHH! about at the redline right before shifting. My guess is that the belt is slightly loose and it is slipping? It feels tight to me but that's not saying much.

Would that be the most likely spot in the rpms?

FYI it does it whether or not the AC is on and ONLY under high load like WOT. If I ease it up to redline, no noise. FYI, SC was rebuilt with new bearings about 6 months ago. Runs great otherwise.

Please help. It is a real burden to NOT drive a supercharged car at WOT

[whitecord]

not sure you will find a lot of info on a e65 b7 in here but i do know if the blower is the problem they are big money. like in the tune of 8 to 9 grand new from bmw.

if it only dose it at high rpm and load it could be related to the clutch on the supercharger