I'm getting earraped by notifications all the time even though in my volume mixer I muted the notifications. notifications like turning on/off my firewall still make an earpiercing noise. I tried turning the firewall on and off while I had my volume mixer open so I could see where the sound is coming from and where to mute it or lower the volume but that didn't show anything.

currently my volume is set to 27% but the notifications still play at 100% which is extremely loud through my headphones
how do I lower the volume of these or mute them entirely?