I assume that you are using plasma 6, the sound you have are played when a device is plugged and then unplugged in loop.
You can disable all system sounds in System Settings->Colors & Themes->System Sounds.
Alternatively if you want to disable only the sound played when devices are plugged/unplugged go in System Settings->Notifications->Application-specific settings ( configure )->Plasma Workspace and search for Device plugged in and Device unplugged
But in your case you should check if one of your devices is not properly connected and do not disconnect, re-connect, it can be due to a faulty cable or usb port…