When using the /playsound command, some sounds (e.g. ambient.underwater.enter) do not get quieter as the player walks away, they even keep playing when the player leaves the radius of the commands location. They only cannot be played to players who are already outside the radius at the time of command execution.

Further example instructions as requested:
1. Place a command repeating command block with the command "playsound minecraft:ambient.underwater.enter master @a" (using master as the sound source is irrelevant, the issue applies with any option) and activate it.
2. Move away from the command block. Hear how the sound just suddenly cuts off when being more than 16 blocks away without getting quieter before?
3. Change the command to "playsound minecraft:block.chain.step master @a"
4. Move away again. Hear how now, the sound will get quieter with distance? This effect should apply to all sounds playable through /playsound.

Video for reference. (Excuse the low bitrate, I didn't want to bother with the 10mb upload limit)