Why does a sound that is not assigned in the settings play when connecting in Windows?

Question

System administration

Recently, a strange sound has begun to play (like piano keys) when connecting in any messenger. I tried turning off all system sounds - it did not help, the sound remained.
How can you understand where it comes from and how to remove it?
Antivirus checked - like clean.
Maybe there are some programs that allow you to monitor where the playback is coming from?

Answer 1

autoruns by Sysinternals
Process Explorer by Sysinternals