Found out why I was getting so much distortion on my radio with my iPod. I had my volume on my iPod full blast. The radio in the Z plugs my iPod in via the headphone jack...it isn't like in my G. Googled and got this info. Thought you might find it useful.
For optimal sound quality when using external speakers, set the iPod volume at less than half the maximum output and adjust your listening volume through your stereo controls. This prevents overamplification, which can cause distortion and reduce audio quality.
