I have had my11 SD XS for three months now and very pleased with every aspect. Certainly more power than my previous TD4 and MPG is always around the 38. The car is very smooth, particularly on the motorway and there is no Turbo whine at any speed.

If it is a production fault, why does it not happen to all? Sounds to me that it is more likely to be faulty part/s which should be replaced under warranty.