Ok Im heading out on a roadtrip from Long Island to Florida with stops along the way and what im looking to do is this: my radio has an rca input, so I want to connect two devices an ipod and audio from a laptop and mix the audio. The reason I want to do this is I have navigation software on the laptop that has voice prompts telling where to turn etc and I was going to put the laptop on the floor or the glove box out out of the way. It would also be much easier to use the ipod mount on the dash to control the song selection and just hear the route directions over the song.