Background noise?

Hello, all. I'm new to high fidelity music listening and recently put together a decent sounding system (for a beginner anyways). And for the moment all my music is being streamed via the Bluesound Node 2. I've only been listening to my new investment since this past Friday and have already noticed that I'm hearing new sounds in songs that I've listened to hundreds of times before. 

One song in particular stands out though: The Doors' L.A. Woman. Because it sounds like there is a tape reel recording in the background. It's most noticeable from my left speaker (if that matters). This is the only song that I've heard this on yet. Anyone have any idea what it is? Thanks.