How to fix sounds for ">:3"'s weapon mods?

I've noticed he's updated a ton of mods that I already have to add new sounds which I was assuming were just replacements over the stock sounds, however all guns that have custom sounds in game now make no noise. Is there a mod I'm missing that is supposed to implement the sounds or am I missing something else entirely?
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All my weapons with custom sounds use firing sounds in stereo.