When I was on a guardian farm grinder, I noticed this bug.

Whenever a lot of guardian death sounds are played at the same time, sound distortions appear for the whole sound in the system (meaning applications other than minecraft are also affected by this)

To test this bug, I went to single player to test this with command:

/execute as @e[limit=40] playsound minecraft.entity.guardian_death hostile @p

The behavior was the same as on a guardian farm on multiplayer.

I noticed two possible sound distortions:
1. After the guardian kill sound is played, every sound in the system is attenuated. Then over a short period, the sound is gradually going back to normal level
2. Apart from the attenuation in point 1, the sound then gradually amplifies further, beyond the normal level it was before the guardian kill sound was played. Then, the sound instantly goes back to normal level

I did not test any other sounds.

I believe this to be a Minecraft issue, because:
1. It happens on two different soundcards
2. This distortion does not happen if this sound is recorded externally and then played outside of the game.

I provide audacity projects and wav files showing these distortions. A 500 Hz signal sine was played all the time with occasional guardian death sounds to show the distortions.