This is a bit of a strange one (T-Mobile UK stock 4.04). If my phone is idle on the table, when I get a message my custom message tone plays, I get a short vibrate, screen comes on. All normal. But if I'm using my phone at the time with the screen on, my message tone doesn't sound and everything freezes completely for about ten seconds. During this time, the phone vibrates constasntly. Once that's done, the message icon appears at the top of the screen and I can read it. Searching, I can find a lot of stuff about an incoming message freeze after you've imported a lot of messages from an old phone, but I didn't do this. In fact, there's only about 20 messages in the memory. Any ideas, please? Thanks!