Hi everyone !
I was really happy because I thought that the last 12.3 update had fixed the speaker cracking problem .... but I still have the problem.
At best I manage not to have the problem by killing the coreaudiod process with the sudo command which is easily found by searching for this speaker problem.
sudo launchctl stop com.apple.audio.coreaudiod && sudo launchctl start com.apple.audio.coreaudiod
(from https://appletoolbox.com/fix-macbook-pro-speakers-crackling-buzzing/)
I also tried to reset NVRAM and PRAM. At best I don't have the problem for 1 or 2 days. But it always comes back.
Last weekend I even reinstalled Monterey (over my macOS without wiping my disk). It worked until today and it's starting again. It looked better but the problem is still not solved permanently.
I just did the last procedure suggested here (delete the 2 files com.apple.audio.DeviceSettings.plist and com.apple.audio.SystemSettings.plist) from safe mode.
I was not able to find the other file you were talking about : com.apple.soundprefs.plist ! I don't know if it's normal anyway, I don't have it.
I just restarted macOS, no crackling on the first minutes but well, it's too early to claim victory.
On machines at these prices, and for a problem that is obviously known (considering all the things you can find about it on the internet over the last 3 years), it's an absolute shame for Apple, and a shame for the rest of us who buy their product to have perfect quality computers!