I recently put a new head unit in my car, and I try to keep it at fairly low volume just to take care of my subs and speakers, but my iPod seems so quiet. Is it bad to use the iPod at full volume and the stereo at half or so, or should I be using like 75% or something on each? It's one of the old iPod videos, with the shiny face, rather than brushed, so I'm not terribly worried about prolonging it's life. Also, to play with the stereo I've been using an AUX cable. Is this ok?