I haven't heard of any of this. The only difference I know of is that the the most current version of the CDSD has a new Phillips transport--which was done simply because Phillips has a nasty habit of changing their transports every year, and the new transport wouldn't fit in the old chassis. According to my dealer, there is NO difference soonically or reliability-wise between the new and old tranports. This USB rumor is news to me, and I try to stay on top of these things.