I had the AUX input installed shortly after I got my '06 S with the H/K system in early May. It has worked perfectly fine with my non-iPod mp3 player all summer, as well as with my minidisc player (has anyone even heard of one? ). Anyway, yesterday my friend and I were about to go cruise on some backroads and I went to play the MD player (which, unlike the mp3 player, I plug into the cigarette lighter), when suddenly the AUX input "mode" disappeared, as in, it would only let me go to the regular radio or CD. I moved the cord that I use to connect the mp3/md player and it would work for a moment, but then disappear and default back to the CD. It almost sounds like a short, possibly being affected by the cigarette lighter, but I'm not sure if this is an epidemic or just a bad installation on behalf of the dealer who did so, which at this time shall remain nameless. I appreciate any input or opinions on the matter.

 

It's a common problem when connecting a player to the aux input and cigarette lighter at the same time. You need to add a device called a Ground Loop Isolator such as this or this. Do a forum search on "ground loop isolator" for lots more information.

 

did this problem just start with ur MD player? or was this the 1st time u tried to use the MD player and have it pluged in the power source at the same time?

 

Thank you for the replies. I had used the MD before, but never for a really long period of time (say, maybe 20 minutes, tops), while this time, I was using it for almost an hour, parked my S, went back to it, and that's when the problem started.
Now, as for the shorting out, would it happen with the rear power source as well? I just thought of that and have not had the chance to give it a shot, although I'm almost positive that the cords on the MD will be long enough to reach. If not, I can live with only the 2,000 songs on my mp3 player, haha, although the ones on the MD are not on the player! Anyway, thanks again for the comments and advice.

 

I used to have a minidisk player... it was supposed to be the new mp3 player.. but the format just died haha, plus minidisk players break so easily, my friends MD player also broke

 

Technically it is not "shorting out", and the problem can also happen if you use the rear power source. When you connect a player to both power and the aux input, you've created an electrical loop that can cause feedback which makes headunit think that aux input is not connected, so it drops it as a selection. This feedback is an electrical noise condition that will happen somewhat randomly.

If you run a search on ground loop isolator and read through some of the other threads, you'll find that some people had used their players fine for months before they suddenly ran into the problem. My guess is that over time wiring connectors in the car do not make as good contact, which causes enough electrical noise to trigger the problem. Using a ground loop isolator has very reliably cleared up this type of problem.

 

I use the Belkin iPod adapter which utilizes both a power outlet and the aux audio input. Anybody know if this is susceptible to the "loop" problem? No problems with this arrangement, but, gee, now I'm worried!

 

I had the same problem with my iPod and the Belkin iPod adapter... It doesn't hurt anything, just unplug the power source and the aux input resets... I now charge my iPod at home though!!

 

Don't worry about it. Lots of people run that type of setup without problem. If it goes away easily by resetting, that is one solution. If it comes back often enough that it is annoying, use a ground loop isolator.

 

This loop thing can happen with ANY external player connected to the cigarette lighter socket from what I've read.
So far it's not happened to me with my iRiver player (crosses fingers), but Ground Loop isolators are pretty inexpenside and can (and should) be hidden inside the dash, so they add no clutter or visible bulk if you need to add one.