You probably know this already, but the iPhone and unshielded speakers don’t mix very well when they are close. It always ends in a buzzing noise. Well, one clever person came up with a solution that’s nothing more than a hand cut Red Bull can and double stick tape.
Of course it’s possible that it will hurt your reception, but it doesn’t seem to be that noticable. Red Bull is optional, any flavor drink would probably work. I think I would prefer a Mountain Dew or Dr. Pepper.