Affects trapdoors that have no block under them. If they have some block underneath then they mimick the sound of that block.
Linked issues
is duplicated by 12
MCPE-190865
trapdoors are missing some interaction sounds
Resolved
MCPE-190880
Trapdoors don't make noise when stepped on
Resolved
MCPE-171773
Trapdoors don't play their respective sounds when walking on them
Resolved
MCPE-131189
No sound of walking while walking on trapdoors
Resolved
MCPE-109586
missing walking sound while moving across trapdoors
Resolved
7 more links
iPad Pro 12.9” Gen 1 on iPadOS 13.4 with Minecraft 1.14.30.
Can also confirmed. I added a video for demonstration.