Check with Auto Toys (http://www.autotoys.com) . They sell all sorts of adapter to connect MP3's and mini discs to car stereos.
From what I've seen in that manual and others about the "AUX on" option, it has to do with the AInet port to RCA plug converter (can't remember the part number but its listed in the manual in the section about turning that option on.
I don't think any Alpine unit in the US has the option to use that particular cable you are trying to use. I've only seen that cable in other countries Alpine sites never seen it listed in the US site.
If I am correct then just go ahead and get the cable that goes with the Ainet port, but if I was you I would just save a little more and get an older cheap iPod and use it with the Fullspeed cable, which will probably have better sound then an AUX to AInet cable with an mp3 player headphone out into it.
Ainet and full speed are 2 different ports, you need this in order to use the AUX input option on that headunit (according to the manual.)
"Setting the AUX Mode (V-Link)
You can input TV/video sound by connecting an optional Ai-NET/RCA
Interface cable (KCA-121B) or Versatile Link Terminal (KCA-410C) to
You can change the AUX name display when AUX IN is set to ON.
Press / /ENT when AUX IN is set to ON, and select AUX Name
by turning the Rotary encoder, then press / /ENT.
After that, turn the Rotary encoder to select the desired AUX name.
If the KCA-410C is connected, it is possible to select two AUX names.
• Via KCA-410C, up to 2 external devices with RCA output can be
connected. In this case, press SOURCE/ to select AUX mode and
then press BAND to select your desired device." http://www.alpine-usa.com/US-en/prod...model=KCA-121B
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