There are also issues with the naming of some files. In my case, I do not use iTunes but I have folders of mp3 songs that have been ripped from CDs and I just copy them over to the SD card. I've seen that some of the filenames of the songs end up being reallllllly long. So I chop off long filenames to shorten them. These files, which previously didn't show up on my list, now show up and playable.

Experiment with renaming the files. Song titles with "01 - ...." in their names may be better served by removing spaces, special characters, etc. You never know if you have a special character in the filename that LOOK like a space but isn't really a space.

Audi seriously lags in the iPOD integration department. Why wouldnt they just create an audio input jack on the radio like most manufacturers? IMO the current iPOD integration package is not good. The SD option sounds good as long as you convert it in the correct MP3 format. I have alot of songs on the POD. Looking into the Nav/SD option. Is the price justified? Will the SD slot be able to read and properly play 2000 songs?

If you have 2000 songs on an ipod and want frequent access to them, the ipod kit is the way to go. It will take 6 SD chips to hold that much music and the nav only holds 2 chips at a time. For me right now, having 700 songs on board is a big improvement over the6 CDchangers I've had for a few years.