Having (some) files unsupported by the plugin but with UTIS included in "public.audiovisual-content" makes quicklook previews/file moves etc hang indefinitely

[AuroraWright]

Maybe related to #112
I noticed that having (as an example) .mid or .sf2 (soundfont files) in my Downloads folder (which I also have as a stack in the Dock) makes quicklook previews hang indefinitely (not sure if only for the current folder, as an example my Dock ~/Downloads stack eventually turns into a bunch of empty boxes) and the affected files can't be moved/renamed etc.
As it turns out, both of those are included in "public.audiovisual-content":

.mid:

kMDItemContentType                 = "public.midi-audio"
kMDItemContentTypeTree             = (
    "public.midi-audio",
    "public.audio",
    "public.audiovisual-content",
    "public.data",
    "public.item",
    "public.content"
)

.sf2:

kMDItemContentType                 = "com.soundblaster.soundfont"
kMDItemContentTypeTree             = (
    "com.soundblaster.soundfont",
    "public.audio",
    "public.audiovisual-content",
    "public.data",
    "public.item",
    "public.content"
)

As far as I can tell, removing the affected files/extensions is the only way to prevent this from happening with the quicklook extension active.