To shorten it: I found all of this.
Music is everywhere. In hotel lobbys, restaurants and in the streets are people playing music. Usually bands with more than 2 and up to 10 members. Here in Germany music in restaurants is usually played by CD and street musicians are playing alone. But in Cuba there were usually bands playing music.
Many of them also try to sell their own CDs. Some CD are homemade, using a CD burner, others are made professional. The price was everywhere the same: 10 CUC, that’s ~ 7,70 EUR or 10 US$.
They are playing different styles of music: Son, Salza, Trova (old and new) and many more. To get an idea, try to find recording of i.e. Buena Vista Social Club. I also found musicians playing traditional songs with a communistic or revolutionary content i.e. “Hasta siempre”.