For the longest time, I used a plain old cassette adapter to listen to my iPod in the car. (It was the cassette adapter that came with my Audible Otis MP3 player when I joined the AudibleListener plan 4 or so years ago.)
I got tired of the noisy playback so last month, I purchased a USASpec PA11-VW to connect my iPod Video to the Monsoon sound system in my 2003 Passat GLX. According to the product description, it would enable charging, playback and control of the iPod through the sound system interface. The product description also said it was compatible with "all 1998-2005 VW radios with a round scan button". Based on that criteria, I was completely qualified. Or so I thought.
After 10 or so minutes of playback time using the PA11-VW, the stereo would spontaneously revert back to the last known pre-iPod state. (In my case, AirAmerica Radio...). The retailer, DiscountCarStereo.com, sent me a replacement unit which delivered the same results. I decided to abandon this product as it clearly didn't work as described. I'm still waiting on my RMA number from them so I can ship everything back to them. In the interim, I've contacted American Express to inform them that one of their merchant's is misrepresenting their products and that I've not yet received satisfaction from their customer service. (Sorry guys, but you haven't responded to me after 6 emails and a bunch of phone calls...)
Earlier this week I decided to try a different approach - auxiliary input into the stereo without the stereo control capability. I purchased a BlitzSafe VW/AUX DMX V.3A Auxiliary Input Converter from LogJam Electronics and I have to say that it seems to work perfectly. Sure, I don't have the ability to control it from the stereo or steering wheel controls but then, I didn't have that capability using the tape deck adapter either!
So now, I get clear digital sound even from the iPod's amplified headphone output. That said, I think I'm going to purchase a PocketDock Line Out USB from SendStation. It not only provides a clean and balanced line out, but can also charge the iPod using a universal USB car charger.