TNT explosion sounds will not lower in volume over a certain radius, and then abruptly fade out and aren't played at all at enough distance

The bug

Explosions are played at a fixed full volume a in 32 block radius. After leaving the radius, the sounds do have a falloff, although only for a few blocks outside the 32 block radius.

Other sounds work as intended.

How to reproduce

1. Have a dispenser fire tnt
2. Start walking away