From earlier phones I have had, I know that if I have a phone near a speaker and the phone rings or get a text message the speakers will make that weird sound. But very often when my new iPhone 4 is just laying there it also makes that sound from speakers. (Not the speaker in the iPhone of course). And I know that it is my phone and not someone elses, becouse when I move it away from the speaker the volume of the sound gets lower and when I take it close again it gets higher. What can I do to stop this. And I'm not even running any apps.