Squeezebox touch. Install the server on any computer in your house that's on your network and hook the touch up to your Integra with digital. If you're going to use Audyssey, the Integra will just convert analog inputs to digital anyway. The ipeng app for the ipad works great.
Some NAS can run the server software, check with Logitech or the slimdevices forum to see what specifically you would need.
I just set one up about a week ago, works great. I'm using a 2TB hard drive into an imac.
I was using my Oppo, but navigating through 50k songs is tedious at best, it's a piece of cake with ipeng.
As a side benefit, I'm using the analog outputs from the touch to run a second zone for outdoor speakers.