Mine does the same thing. 2009 E92 bought new, started noticing it after couple months of ownership. 3 years later w 60000km w/o any issues, have learned to live with it by adjusting the timing when I press the clutch when the car slows down. I know you all said its normal for this MT, but does anyone know where the sound is coming from, clutch, diff....? and how the sound is created?