Um, yes, the sound system in the S, especially our first one, was so terrible that if I were Tesla, I would quietly scramble to improve it without mentioning a thing. .
Either there is something wrong with your car, you're listening to bad sources (like Slacker, TuneIn, or low quality digital), or you want the bass to be the only thing heard. I have a fairly old (now) Studio Sound System, and it's great. Hundreds of people have sat in my car and many have commented on how good the sound system is, including the guy with the Bentley and some sound engineers. Not one person has complained about it. Now I don't doubt that a $5k+ Reus sound system it would sound better, but the premium sound package seems just fine to me.