I have Notifications Sounds disabled (off) in System Settings, yet I was surprised (literally) to hear an error bell though my stereo. Is this a Plasma bug, that not all applications are prevented, or is Dolphin not considered a System app? That makes logical sense, but is there a way to shut off all utility error sounds? I realize Linux is an ecosystem, but I thought it was centralized enough for that. If nothing else, is there a way to disable the Sound in Dolphin? Or maybe something akin to Window Rules or a way that I could whitelist applications allowed to connect to Pulseaudio?

I found another Bell under Accessibility > Bell > Audible Bell

echo -e '[Bell]\nSystemBell=false' >> ~/.config/kaccessrc