You can now play a sound when a command is blocked.
The "sound" uses Bukkit's Sound enum, since XSeries does not support 1.20.6 currently. This can differ between versions, so you'll want to make sure the list you are using is for your Minecraft version.
1.8: https://helpch.at/docs/1.8.8/index.html?org/bukkit/Sound.html
1.20: https://hub.spigotmc.org/javadocs/bukkit/org/bukkit/Sound.html

Pitch and Volume values are floats that can range from 0.0 to 1.0.

API Notice
As of this update, we have renamed a number of methods to be more consistent with the Spigot ecosystem. The previous names are now deprecated, with removal planned within the next few updates.