Been playing with my 'audiophile' system and have connected my iPod to my 4400 via the dock. This allows remote control but also gives better sound quality. I use BBC LS3/5A speakers with an AB1 woofer under each speaker. If you have not heard these little speakers, try to! They are no good for very loud or parties but for the human voice and classical as well as jazz and everything below heavy metal, they are sublime. Beautiful open sound and the soundstage seems to be wider than the speakers! Quite frankly, for a vintage system in a small to medium room (our bedroom is 15 by 20 feet), these are the best I have heard. Have a look at the Richard Allen site for details if you are interested.
The iPod has 160Gb of music recorded at good quality and sounds great through this system.