Mine only does this when I accelerate from a stop position at light throttle. Heavier throttle positions and it's a smooth operator. It does this more then its colder outside, but as it gets above freezing, it dissapears. It's not a clutch slip issue, it shifts and holds fine in all gears and will sure bang shifts in S6, it's just that initial acceleration and it only happens in first gear up between 1,000-1,800rpm, but not in second gear. This might also be called clutch chatter.
I've disconnected the MAF to see if thats a possible cause, nope. I have new spark plugs, ignition coils, fuel pump, fuel filter, air filter. I've tried the SMG reset, so I guess my only solution would be to check for a software update from the dealer.
E92 335i 6spd
BMS JB4 stg 3, BMS DCI, CM methanol injection
04 M3 sold
03 330Ci sold