I have a nice 5.1 home theatre system. Yamaha RX-V471 receiver, Samsung Blu-ray DVD player, Apple TV v2, Mirage 5.1 speakers, iPhone/iPod, and a beautiful new Samsung 55" LED TV. Sound quality when watching HD movies is amazing. I love it. But sound quality when listening to my iPhone/iPod is so-so. What am I missing here? Would the addition of a DAC enhance my current arrangement? If so, where does the DAC go? In other words, do I plug my iPhone/iPod into the DAC? If so, how does the audio get from the DAC to my receiver? Please help me understand how this stuff all works together. Many thanks.