To duplicate:
Place a Dropper with a rail in front of it. Then put a hopper cart on the rail. Then put something into the Dropper. Power it, then see that there's no sound for the Dropper triggering if there's something in it.
MC-7723
Dropper makes no sound when placing item into a container
Resolved
Works As Intended
3
Confirmed
minecart, sound
Snapshot 13w03a, Snapshot 13w04a, Minecraft 1.5, Snapshot 13w11a, Minecraft 1.5.1, Minecraft 1.5.2, Snapshot 13w18c, Snapshot 13w19a, Minecraft 1.7.4, Minecraft 14w08a
Retrieved
This is also true of a dropper into a chest, and trapped chest.