Mutes the sounds produced by Pistons and Sticky Pistons, without affecting other sounds.
Version 1.9 and above supports changing sounds using json files, decreasing file sizes and increasing performance.
Versions below 1.9 use the only way to do this, a 0 seconds mute sound replacement and might require a game restart.

Click here or on the image above for the Quieter version
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Mute Dispensers and Droppers Quieter Dispensers and Droppers
Old Water Old Bedrock New Bedrock

Vanilla Hearts HUD Vanilla Hunger HUD