I purchased an Aurender S10 used about 6 years ago and it's been great. I think it was about 5 years old when I bought it, so I'm anticipating the day I go to listen and it's dead. I only use it as a music server--I don't stream any music on my 2-channel system. What would be the natural replacement? What improvements can I expect from a newer, more expensive, and presumably better server?