I tried the FM wireless modulator with the factory unit. It was so bad I didn't even leave it hooked up for 10 minutes. Then I tried the wired FM modulator. It wasn't much better - in fact I couldn't tell the difference. The thing is, the FM signal seriously chops off the frequency response range and you just don't get the low's and highs like you do with a CD or other high quality sound source.

I spent a lot of time looking for a way to directly connect an iPod to the factory stereo and I can tell you with great certainty, it isn't easy and for what it supposedly costs, you can get a much better head unit and get better results. In the end, the only reason to do what I found was to keep the factory look of the stock head unit.

Basically the theory is that you have the head unit flashed so it can support a CD changer. Then you buy a CD changer emulator that gives you AUX inputs. Then you plug your iPod in that way.... Flashing (if it's even possible) at a Porsche or VW dealer (if they'd even do it) could cost you a couple hundred dollars. Then the CD changer emulator sells for about $300... So let's say you actually could get the head unit flashed and it came back working, and the CD changer emulator wasn't a piece of junk and could be hooked up. Now you have $500 into this and all you can do is plug in the iPod but you can't control it through the head unit.... See what I mean?

In the end I took the head unit out, carefully set it aside for when I sell the car, and put in something that lets me run the iPod directly with the head unit. The sound is killer.

Have fun doing the research - it kept me busy for a week. Then I wrote a check and installed a head unit. That was a lot quicker and more worthwhile than all the dreaming about what I could do to the factory unit...