Prior to getting the iPhone a little more than a year ago I had been a long time Verizon customer. I still miss their excellent East Coast network. The switch from CDMA to GSM brought an unwelcome addition. Noise. Noise in all kinds of speakers. I have to put my phone in the cupholder in the car. If I put it any closer to the radio you can hear it. That rapid fire chirping. It keeps going and going...then it stops and you almost think, maybe it'll quite for a while...then bbrrrrr,brrrrrrr,brrrrrrrr. Agh!
The thing that drives me the most crazy is the Cisco 7940 sitting on my desk. I've moved the iPhone to the opposite side of the desk. I've tried turning it this way and that. Tried moving the 7940 around. Best I can hope for is a faint buzzing sound. It only comes out of the speakerphone, not the handset itself. But it's there...driving me crazy!
The only real solution I've found is to have something in between them that will soak up the radiation. A 20" LCD doesn't do it. No, I've not found a consistent trick yet. It's my mission now.