In the simplest way, do sym.play(0); for the stage symbol.
If it's not good enough, let us know.
It depends what you are doing. sym.pay(0) might not work if you have lots of things going on. In the case you do, you may have to reset all symbols to play(0) and reset all sounds, etc... It is not always that simple. Sometimes I choose reload because it is easier. Sometimes I write a function that includes all elements that have to be 'reset' and just use the function on a reset button.