It might not be the audio itself, but terrible processing and all those ‘effects’, as said above. Lemme repeat myself once again: clear audio files for cards sound just fine in the wiki, but not in the game (or on top of the background tracks, resulting in ‘DEEYALO-MOOTO-DYTHOO!’ or ‘Cult of N’Zoth!’ instead of ‘Cataclysm!’ for Deathwing, Mad Aspect).