Volume slider in Volume mixer goes to 100 at random times.

At seemingly random times, Discord's volume in Volume Mixer goes back up to 100. 

It could be after every update, though I didn't pay attention, it seems to be after SOME amount of restarts of my computer, not every single one. 

Is there a permanent way to fix this so it can stay at my desired volume or do I have to manually check it at all times? I have that “Discordo!~” sound on when I open it so I'm not surprised by the high volume when entering a call, which means I always get jumpscared when it plays randomly at 100 volume.