I was looking at the files that I downloaded in my phone when I updated the music pack and I realized that in the Basalt Deltas biome some ambient sounds are missing, these are the missing sounds:
Basalt deltas active 1
Basalt deltas active 2
Basalt deltas active 3
Basalt deltas active 4
Basalt Deltas Basalt Ground 4
Reference:
https://minecraft.gamepedia.com/Ambience#Basalt_Deltas_ambience
Linked issues
Comments


Affects 1.16.210.54 Beta.

Affects 1.16.210.55 Beta

Affects 1.16.210.57 Beta.

Affects 1.16.210.59 Beta.
Thank you for your report!
However, we're already tracking this issue in MCPE-79532
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Affects 1.16.210.53 Beta