You'll get better reliability running VGA/DVI/audio cables than PCI extenders. They push a lot of data and power over those PCI connections and they aren't designed to be put too far from a processor. I have successfully extended VGA video more than 25 feet. I bet you could do even more with DVI.

If you want a more remote sound solution, you could go with an external, like
http://www.amazon.com/Creative-Labs-...5810233&sr=8-1

electrical tape should set you back $0.99 and you can splice all those little wires to your heart's content... power, power switch, HDD, reset, etc. You should be able to run those a huge distance without problems. You'll probably want to splice some of them to existing switches in the jukebox anyway.