try changing the windows state on the bottom right to hidden, minimized, maximized.. try them all and see if that does an option. Also, when I had this issue I remember that pressing "enter" on my keyboard made the sound start working. maybe it wasn't enter, but it was a key on the keyboard.
Also, the cps3 emu does skip the hour load, but on mame you only have to go through that once. there's only a few cps3 games.. just do it for one game go and do something else and by the time you come back it'll be done. It's not that bad.