Classic WoW

Since the release of TBC the new MuteSoundFile API was added to the classic client, the retail version now works for both versions.

Custom sounds mutes:.

If you want to mute sounds that aren't already included in the addon I've created a small tool to help you do so using sound ids found on wowhead.

To clarify, this is NOT needed to make this addon work, this is something extra and entirely optional for those who'd like to mute sounds not already muted.

The download and instructions for using it can be found here:
https://github.com/Kiingy/MuteWoWSounds.

The above link also contains the complete source code for anyone interested.

Basic List: Please note this isn't a complete list, it's a small sample to give an idea of whats been muted.

Players: All race combat grunts as well as emote sounds like train and worgen sniffs. All footsteps.
Classes: Select sounds like Path of Frost, Fan of Knives, mage armors & portals, hunter pet calls, shaman shields and spell cast fizzles.
Mechanical Mounts: Choppers, Flying Machines, Goblin Trikes, Mechastriders and Rockets.
Biological Mounts: Summon roars, mount special, idle and footstep sounds for most mounts. Dismount sound also included.
Battle Pets: Idle sounds like Lil'XT, Lil'Ragnaros, Singing Sunflower and Thor.
Hunter/Mage/Warlock Pets: Creature combat sounds, footsteps, flying and idle sounds. Mage elemental loops also included.
Voice Acting: World bosses, Rhonin & Kalecgos city speech and Headless Horseman speech.
Toys: Piccolo of the Flaming Fire, Train Sets and Brewfest Mole Machine.
Daily Hubs: Isle of Thunder, Isle of Quel'Danas and Tol'Barad.
Misc: City clock sounds, ethereal vendor hubs, waterfalls, rivers, beaches, fires and fireworks.
Battlegrounds: Victory/Defeat, Alert and Herald sounds.
Instances: Select boss speech and combat sounds, loops sounds like the beating heart from SoO. All instance portals.
Creatures: Kovok, Elemental loops and deaths.
Tradeskills: Alchemy, Leatherworking, Engineering, Blacksmithing, Tailoring and Jewelcrafting sounds.

Mute Annoying WoW Sounds