I'm dismayed that the iPod nano dock connector audio output is not effected by the iPod software volume control. Is there any way around this? Or is there an alternate design for the following:

I designed and began creating total factory iPod integration for my sister's 1993 Volvo 240 wagon. It has separate amp and headunit, so I planned to put a source switcher between them to allow iPod aux in. Instead of using the lame headphone jack, I planned to use an iPod dock connector to RCA and power connector to fully power and get audio from the iPod.

Unfortunately, the iPod volume control doesn't effect the dock connector audio output. So, it blasts at full amplified volume (which isn't painfully loud, really). Using the headphone jack, even through the amplifier with iPod volume at full blast, is too quiet.

The only redesign solution I can think of is to add some volume control between the source switcher and the amp. Then, leave the stock radio on full blast, let the iPod be on full blast, and use this other volume knob. I have no idea how to create that and would rather not have a separate volume knob. I'm trying to keep this looking totally stock, so that would ruin it.

It's a silly plan. I should just get an Alpine with iPod input, but my sister wants to keep everything totally stock. Seemed like such an ellegant solution.....