Don't reset sound level when generating sound

[MarcusOtter]

If I change the gain slider down to something like -20db because it's loud, I don't expect the volume to reset and be loud again when I randomize or select a new sound. It makes generating multiple sounds very difficult as the volume has to be modified on the operating system instead of using the built-in volume slider.

[chr15m]

Good idea, thanks Marcus.