v1 gobbles up the entire DMA buffer at once, v2 eats it up in smaller chunks (the real hardware actually eats it up byte by byte, so v2 is more realistic, in between v1 and the real thing).
Dragonsphere and Phantom for some reason corrupt the audio buffer as soon as the first DMA xfer is made. Doesn't matter with v1, because v1 will copy the entire buffer during the first transfer (after shich the game can do whatever it wants with the data, v1 doesn't care, though v2 *will* care).
I thought it was a bug in Windows' DMA, but if DosBox has the same "feature" then it is possible that Matt may be using some undocumented or non-standard stuff (though, again, Rex Nebular does not have this issue which is strange).
Funny that any of the three Matt G. games would work with DosBox, BTW -- I was pretty sure they used protected-mode.
V.