As most of you have already seen, a few days ago Haze released an update with the first version of my NMK004 simulation code.
All NMK004 games have sound, though in some of them it's better than in others. Mustang is possibly the worst one - I have doubts about the sound ROM being a bad dump.
There were a few major problems - music stopping shortly after starting, or games completely freezing MAME. I have found a bug in the loops handling which should have caused most of these problems. Here is the fix. It doesn't improve Mustang, though.