kenwood KMD-673r AUX

hi, i have a kmd-673r head unit. (i know MD's, who has them anymore, but apparently i do). anyways.. i recently bought a cable off ebay to connect an ipod through the head units cd changer port. i plugged it in and everything the ipod charges. but i have no idea how to listen to it on the unit itself. i cannot find an AUX source in the list of sources. i have googled around and it seemed like alot of people are having this issue and you just have to turn it on by "setting it to stand-by, hold menu and scroll through it to find AUX on/off." the problem is i dont have this AUX on/off setting. can anyone help me out on how to turn the AUX on? and i really dont want to change the whole unit out either..

this is what my unit looks like...

http://www.minidisc.org/images/kenwood_kmd673r.jpg

try this link for users manual

http://www.minidisc.org/manuals/kenwood_kmd673r.pdf

yea i have already went through the instruction manual several times. it says something about a O-N switch. i am assuming that is on the actual cd changer box not the head unit since ive looked all around found no switch.

i have also tried plugging my ipod into the RCA ports (the red/white ones) in the back. it would play through those but it only works on the back speakers and would play over the radio. so i hear two audio sources, the radio and the ipod, at the same time.

On page 6, there is information that points to an adaptor kca-s210a that you may need for switching components. Other than that, I'm not sure what else you can do.