I have a MacBook Pro 15" without the ExpressCard slot. I've been doing research since I got the computer (and even a little before) about any external soundcard solution using either USB or FireWire to make my music sound better. There are so many options for Windows, but none for Mac. It's incredibly frustrating. All I want is the ability to hook up a 5.1 analog speaker set to my Mac, with good quality output. And if I have a 2.1 system, I want it to sound better than the Mac's built-in output. Do external soundcards for Mac even exist below $500???