Our Sales teams use the 6915 mainly for remote email connection and TOMTOM. However one of them is experiencing this problem where the phone service is disconnecting from the network. I have contacted the service provider and all seems ok with his account. He gets a strong signal in most areas and we have tried tried all the standard remedies - removing battery and SIM without switching off, soft reboot, manual roam and connect etc. Is anyone else experincing a similar problem? If so; any suggestions?