Sound issue - I hear everything even underwater

[Pillar]

I did a search for this but I didn't find anything, so I assume it's okay to post. (?)

The issue is that I can hear all the sounds, environmental or otherwise, no matter where I am. I can be 150m depth and still hear everything loud as ever.

Apart from being able to hear everything, and loudly, all the sounds are also very garbled together. There is what sounds like a loud engine noise (again, even submerged) and airplane noises as they fly overhead.

Any advice on how I might solve this, or what might be causing it? I'm patched up to 1.4b.