I was annoyed by a night walk ever present background ambient music coming from houses, Copy/overwrite it inside the game directory to a folder (better backup the original one)

x64/audio/sfx/STREAMED_AMBIENCE.rpf

That's all.
Read the next additional lines only if you want to learn how to adjust this mod or create own sound mod:

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I followed the music change manual, generated 10 seconds long silent wav file, exported oac files - in same parameters 1 channel, 8000 hz 16bit wav file, as were the original ambient music sounds.

Similar approach as https://www.gta5-hub.com/misc/no-distant-car-sounds inspiration.

Tutorial: https://www.youtube.com/watch?v=ymLrNTjGBXA
(How to edit GTA V audio files in OpenIV (.awc))
https://github.com/FantomX1/AmbientBackgroundMusicModOAC
Also github library, for adding yourself only concerned files, being smaller in filesize not affecting everything combinable with other particular changed sound files mods or lower chance of affecting new GTA5 updates

It is enough in edit openIV app mode to drag and drop the .oac files definitions to affect particular sounds