Audio Output problem when connected to car port

Just switched to an iPhone 4 from the 3G model. When I play any audio (music or Pandora)while connected to my car port, I get bits of noise at timed intervals coming throught the speakers. I would say it is about every 2-3 seconds I get this little added noise sample added to the audio stream. My old phone and ipod classic work great so I know it is not the car deck. The headphone mini connector produces clean audio.

Anyone else have this?
This in addition to the other problems that seem to be inherent in this new device has me thinking about returning the phone tonight.