At the bottom left of your screen you will find a gear in a circle. Click on the icon. Click on the speaker icon and the music icon. You should not have any more music and sound effects.
The only problem with that is it seems to reset every couple of log ins, and I'm not clearing any cookies. It just seems that it randomly turns itself back on every so often. It happens at least once a day. . Annoying is an understatement.
