I'm not sure if this is still being developed but I like the concept of this and don't want to see it die. When I type sounds.radioLoadSound() and press any radio button, I get a fatal vehicle exception.
I hate to tell you this, but it looks like it has already died. This is called bumping. The date of the post before yours is May 22, 2016.
Either way, I'm surprised that nobody else has tried to do something similar. Makes me sad since it seems like such an obvious mod