Steps to Reproduce:
Step 1: Place a random block, then place the birch hanging sign to the side of that block.
Step 2: Place a noteblock on top of the birch wall hanging sign.
Step 3: Press F3, then point to the noteblock, next check the instrument block state of that noteblock.

Observed Results:
Birch wall hanging sign use "snare" instrument when place under noteblock.

Expected Results:
Birch wall hanging sign use "bass" instrument when place under noteblock.

Notes:
This only works for birch wall hanging sign, as the other wall hanging sign, non-wall hanging sign (including birch) will use "bass" instrument.