Are there more than one version of SB live value? The picture on the creative web site shows no digital output, while people talk about the digital output from SB live value. Looks like I can pick up SB live value w/o digital output for $43, and some guy sells SB live value w/ digital output for $48. Are there any other difference between the two cards? And if I buy the one w/o digital outpu, can I add on the digital output later? Thanks.