I should qualify my previous response with a caveat. I have noticed non-bit perfect results on machines that use the Via southbridge chip and 4-in-1 drivers of the type that were commonly used with Athlon processors about 5 years ago. In those implementations, all PCI bus, USB and ISA bus traffic goes through that same chip and they all share a common interrupt. Sometimes, an interrupt is not serviced soon enough and the result is dropped samples. In machines like that, you have to do the transfer at least 3 times and trim all 3 copies to exactly the same starting sample. Then you compare 2 of the copies to find where they first differ from each other. Then you refer to the 3rd copy to find out which of the first 2 were correct, make the require change to the one that was wrong and repeat the procedure until all of the differences between 2 of the files are resolved. The original transfer will not be bit perfect, but the end result will be bit perfect.
FWIW, I've also had the same experience with the Audiophile 2496 that everyone claims to be bit perfect.
Bottom line is that I've found both the Audiophile 2496 and the Audigy 2 series soundcards to be bit perfect, but some computers that use Athlon processors and a VIA chipset may drop samples. Usually the dropped sequence is less than 5 milliseconds in length and typically are 1 to 1 1/2 milliseconds in length. If you have a computer like that, it's unlikely that any particular soundcard will cure your dropped sample issue. You either have to deal with it by comparing multiple copies or you have to replace the computer. (I chose to replace the computer.)
Topic: Audigy 2 zs bit perfect or not? (creative labs quote inside) (Read 3001 times)