I have redone several of the commands to be standalone, as in instead of "Music, Volume 40", or "Music, Previous Track" It is just "Volume 40", or "Previous Track".
Just changed it from command suffix to full command and deleted the Music prefix. If it is triggering on other words, maybe bump up the minimum confidence level.
My reply above was more for the fact that the plugin is a hit or miss when it "hooks"
I can use the commands and change volume, and can see the volume slider move in the volume mixer in windows, but it can take 1 to 10 minutes for it to actually effect spotify. Once it hooks it is fine, but until then it is just giving volume commands until you hear a change.