This is due to the way the mod is currently handling sound source code. It has hard-coded a value of 16 blocks away. Please extend this value so that even Ghasts can be culled out or add a whitelist to make sure sounds with higher volume can be chosen to be culled or not. It seems to be specific to entity emitted sounds, such as Ghasts. Explosions were not affected.
Note that the issue is shared by Dynamic Surroundings, this mod would be the first to fix it if implemented. Sound Filters mod functions perfectly fine
https://github.com/Exploding-Creeper/GunsWithoutRoses/issues/4
This is due to the way the mod is currently handling sound source code. It has hard-coded a value of 16 blocks away. Please extend this value so that even Ghasts can be culled out or add a whitelist to make sure sounds with higher volume can be chosen to be culled or not. It seems to be specific to entity emitted sounds, such as Ghasts. Explosions were not affected.