You could try setting up a Sound Blaster driver in Windows 98's Device Manager, I'm not sure if that gets true the virtual layer but it's worth a try.

But since there's no way to set speed, I think you're bound to old software based solutions. I remember a program called 'MoSlo' that can slow down the system to play older games, and there's VDMSound that can emulate a Sound Blaster though I think that was for Win2000/XP only.

My recommendation is to either create a new VM with just a native MS-DOS, since Jazz1 was supposed to be played with that, or stick to DOSBox and try to optimize dosbox.conf to match JJ1's specification. I'm not familiar with Parallels Desktop so you'd have to peek if it's possible to have a virtual sound driver for DOS that passes Sound Blaster.

For DOSBox, I highly recommend setting these dosbox.conf changes for Jazz1 to make it look like it's played in the good old days:

fullresolution=Your native resolution
output=ddraw (opengl could perhaps be better for MacOSX?)
scaler=normal2x
cycles=fixed 6000 (6000 cycles is exact speed for Jazz1)

For sound, Sound Blaster 16 is the standard option for DOSBox, but it could emulate Gravis Ultrasound using the config setting. It was supposed to be the best sound for Jazz1, but I never used it.