Ok, I got a chance to look at it today. I went to CD/Multimedia.
Then to External Devices.
Then I clicked on the iPod. It started to play, so I went back.
There was no options for Aux volume. So, I pressed option and got...
Trying a different way, I went to the main menu.
I went to Tone.
Then tried Volume Settings.
But the only things there are these.
Anywhere else I should look?