I will be taking the plunge into the Mac world soon (a Macbook Pro with intel processor) and long overdue it is too. I am looking for a USB sound card to enable my 4.1 speakers to be taken advantage of.

I have done some research and found a couple of cards but I am somewhat unsure of them. Basically all I really want is a usb sound card which will upmix stereo sound to my quadrophonic speakers.

I am looking at m-audio Sonica Theater but it looks a bit old and I am concerned whether it will run on the newer intel processor setup (the site only appears to have drivers for PPC architecture). I also saw the Sitecom USB 5.1 Channel Audio Adapter (http://www.usbgear.com/usb-audio-adapter-5/index.html) but I am not fully sure if it is Mac supported.

Any help here would be great, ideally if it works I think I would opt for the Sonica Theater, otherwise can anyone suggest a viable option for about 50?