OK the phone is back with Carphone Warehouse, who are sending it back to Nokia to be repaired... 10 day turnaround I also dropped in to the local Nokia dealers, they confirmed that this is a problem with the earlier models, but that it is fixed with later ones?

If it goes again I will ask Carphone Warehouse for a (later) replacement model. 3 strikes within 3 months is enough to ask for a replacement, isn't it?