Try this first...
"if you want your machine to have reel sound open he door, press the self test button you will see a 2-0 push the spin button you will get a 2-1 then close the door and it will have sound.
be sure their are no credits on the machine."
The test button is a very small white button. Its usually located on the back of the interior on/off switch but some games have it in different locations.
Then this...
"Depending on the SP chip in use, you may have to reach zero credits (play them out or cash them out) before the new dip setting will take effect. In addition, newer SP chips ignore the dip switches and use a setting to turn reel sounds on or off. "