It turns out DVDs are the only way to watch season 1 as it was intended to be seen: with the original music. Pretty much all the music on Netflix has been replaced, certainly all of the tracks you know and love. Whether it's your first or 50th time watching the series, believe me, this is not the way to go.
As the licenses for the site to host various productions expire and get renewed, they are removed and then periodically reinstalled. But some people are now noticing that the soundtracks to TV shows available on the service are being changed, and very few of those people are happy about it.