you can jailbreak or otherwise partition the OS to allow additional menu options to load other software... in this case XPMC so you can stream all your music and video file content stored on any other computer on the network. I've done it with original apple tvs... the processor/memory in them isn't fast enough to stream HD video content, but it works with audio files... not the best sounding option out there, and the remote is awful, but it works....
you just need to bite the bullet and put a laptop or desktop in the audio chain and use a USB cable to connect to a DAC with USB capability. It couldn't be easier.
Software options are plentiful, from free (Foobar2000, media monkey, etc.) to paid (JRiver Media Center)....
Someone recently released a new, free room correction plug-in for Foobar2000 that has been getting good reviews:
http://mathaudio.com/ I'm curious to try it myself at some point....
JRiver has a lot of EQ capability built into the interface that does everything in 64-bit depth... which should mean it doesn't affect sound quality.... too early to tell on that one for me from the little bit of playing around I've done..
I prefer foobar myself, but Jriver can be nice if you like more visual representation of your collection...
seriously, it's a couple hundred bucks to build a pretty quiet PC. If you have a TV in the room with HDMI capability or D-sub 15 vga connector capability, it becomes your computer monitor.... they are selling wireless keyboards all the time for half nothing.... you sit on your butt in your chair and have control of your entire music collection at once.... if you don't have a TV in the room, programs such at Teamviewer offer free remote desktop capability so that you can still sit at your chair and use a tablet or phone to control the computer remotely.... I do both options currently. I use a Microsoft Surface tablet and TeamViewer to connect to every computer in the house and execute various tasks, including controlling the audio PC in the two channel room... or I just use the wireless keyboard connected to the PC and the computer monitor I have sitting on the end table next to the main listening spot couch...
it seems intimidating, but once you have it fired up, you'll never go back to just spinning disks.... I've always kept a transport around to spin disks because ulitmate sound quality was still on the side of the spinners.... the latest software and USB implementations have made it soooo close, it's hard to ignore the convenience factor of the PC, especially if you have any kind of high-rez collection....