Lag or improper configuration?

[Ralnir]

So keep in mind that I'm testing this on XM6 TypeG because I'm not sure if I need a separate harddrive or how to transplant it on one I've already set up or what, but that's besides the point for this question. Hope it's not against the rules to ask questions about non-genuine operation, but that's enough faffing about with words. I have a digital copy of Street Fighter 2 in SASI harddrive form and it runs, but it seems to grind to a halt when playing special sound effects, like it's having to search the sectors on a really old harddrive to find them.
I get the impression that I wouldn't have these problems if I put it on the real X68000, hardware considerations aside..