I have been trying to set up VA to be able to mute and unmute the Pandora application on my PC. I tried the command several different ways (setting volume level, muting the app, unmuting the app, toggling the mute state of the app) and nothing worked. But finally, when I tried the toggle command, I got an error. It would recognize the command and then immediately say "Unable to toggle application mute". At least once when it printed this error, it also printed an Exception but unfortunately I did not get it copied down.