My Doro phone will often cut off at point of contact - i.e if I answer a call the screen goes black for a while and I can't hear the caller when it comes back on there is a red cross in top right corner of screen. Same with some texts it starts sending them then screen goes black as above - it comes back on but the phone does not show them as sent but some people do get the message --- others don't... it happens in all locations not just poor signal areas