Sorry, I seem to have misread something earlier - I'm actually confirming this for Monkey Island 1: Special Edition. I assume MI2:SE it has the same audio engine since this is a series by the same creators. It seems that the bug report is exactly correct - I can only hear sound when the frequency is set to 44100 Hz and emulation mode. I'll probably buy MI2:SE (for Steam) a bit later this month, but I'm pretty sure the problem and the fix should be the same for both games.