MC-171366 may be causative of this.

When a fire block (or equivalently soul fire) is broken by hand, a hissing noise plays, equivalently to the breaking sounds of other blocks. However, when broken with a setblock command with destroy specified, the fire block just disappears without making a single sound.

A screenshot of breaking sand under the same conditions is shown - note how Block broken appears in the subtitles of said screenshot, signifying that the sand made a sound.

To reproduce:

1. /setblock ~ ~ ~ fire
2. /setblock ~ ~ ~ air destroy
3. Observe total silence