Come on guys... This can't be too difficult that I have you stumped...
An Apple Airport Express (AE) is the best solution. You can transmit a wireless signal from the PC to your stereo so no need to run wires. There is a a $39 remote that works through the AE to control the music from your listening room.
The Airport Express has a digital optical jack so you can use the DAC in your Cary. The sound quality is absolutely amazing.
You will need the Airport Express, iTunes software, the remote. If you don't have a wireless network, you will also need a card for your PC. The AE comes with a digital cable which I hear is OK but you may want to upgrade to a used cable for $70 - $90.
I use this set-up, check my system for details. I do not have an optical input on my CDP so I had to add a converter into the mix. I got a Monarchy DIP for $200 and it is a great solution although there are other less expensive converters you can use.
I bought the $50 version and use the little DAC that comes with it. I bought it at Circuit City thinking I could return it if not satisfied. It was a no-brainer to keep it. Instantly I knew it sounded better than the y splitter cable I had been using to connect my computer speaker output to my aux inputs of my stereo. Yes, better bass and more musical.
The $100 version looks light it comes with a little more substantial DAC even though it's probably the same chipset. Would get better fidelity using your Cary dac? I don't know. Just buy it somewhere that has a good return policy and play around with it. There may be other solutions, but this works well and was easy. I have a home office and listen all day long. Good Luck!
The AE does not have a digital coax out which I found out AFTER I picked by DAC so I had to buy a used Monarchy Upsampler and another cable for about $300 more. You can get an older Monarcy DIP for about $100 on th is site and a used cable for probably $50. There are other options. You can get your AE modified and a coax jack added. I do not know the cost. There is an audiogon member that does it (Audioengr) Or you can get a converter for about $50 but I believe the quality would reflect the cost.
Another option is the new model of the Squeezebox. It is a one box solution for $300. It has both digital output options.