Well, the music now works! At first the speed was really slow, so I had to finally determine the speed of the 80c32 CPU and the Sound chip.
It turns out that the cpu is exactly 7.3728 MHz or (2 x 3.6864) and the sound chip is 1.6666 MHz or (20.000/12). These values line up nicely with the crystals found on the motherboard (3.6864 and 20.000).
I found there are 5 tones and 9 songs. The 9th song is not played during operator mode, but is used I think when paying out credits or coins. Its just a song where the notes keep getting higher and higher. This seems to match how the payout process works.