The Bug
Sounds partially break down within the vanilla world border in 1.20 and 1.20.1 (much worse outside of vanilla bounds). Probably caused by an improper float cast. MUCH EASIER TO NOTICE WITH HEADPHONES.
How to reproduce
Put on headphones.
Trigger sounds at spawn (ex. breaking blocks)
Teleport to a high distance such as 30000000
Compare the two, and you will notice that the sounds farther out sound glitchy and distorted
Easiest to notice by breaking grass blocks.
Linked issues
duplicates
Comments

Does MC-191170 describe your issue?

@markderickson Yes, but it seems to have gotten much worse in 1.20 and 1.21. You must remove the world border and teleport out into the billions to even notice it in 1.19.4, while in 1.20.x it is now extremely apparent once you pass 1677716. (while in 1.19 it is barely noticeable at this distance)
Thanks a lot! Could you add that to a comment on that report, please? We can update it once you do – that issue seems to have grown, which has been recognized on that report as well.

@markderickson Done.
8,388,608 is the exact distance at which this occurs past. Slightly more distorted once you pass 16,777,216.