Not knowing how the game handles audio files I'd like to ask whether it's safe to remove audio and lip sync files from a mod, or will the game crash when a non existant audio file is called?

In this mod: http://www.nexusmods.com/oblivion/mods/46201/?Mages Guild Improved (Verbasserte Magiergilde EV)

there are sound files and lip sync files in folders named with the name of the plugin and also some sound files in folder fx. They are in German, while I play English version of the game.

I checked out plugin in TES4Edit and wasn't able to find reference to the files. I suppose that they are used in dialogs but no reference in the Dialog Topic field.

I use Elys Universal Silent Voice if that matters.

It is safe as far as I know.