Regularly used BtSmartTalk without hassle up till today. Now (just before I'm setting off for Europe!) it's decided to stop all sound within 15 secs of connecting and dropping the calls about 45 secs after that. During this time all buttons are frozen. iOS7, home wifi, connection tested. I've rebooted the phone and deleted about 800 pics in case it's a lack of memory problem. Any other suggestions?