I don't appear to have call waiting in operation. But, more than that - I seem to have an issue where, if I'm doing something on the internet (e.g. checking email), the call doesn't come through. Take, for example, a mild incident today: Meeting my beloved mother, for once in her life she's remembered not only to have her phone, but to have it on (will miracles never cease!). I call to find out where she is. She's 5 mins away. So - while waiting for her, I go into my gmail to respond to a mail. Mother arrives - 'I tried calling to say go queue for a coffee, so we didn't have to wait, but it went straight to voicemail'. I hadn't moved, reception was still good. BOO HISS ETC. What's going on?