This function mutes all speech and audio of a specific speaker client (host or host:instance).
Parameter: host
Type: string
Description: Leaving this a null string will mute the first instance HomeSeer
finds, otherwise use the hostname of the computer you are interested in
muting. If
more than one instance of the Speaker application is running on "host"
then you may need to specify the instance as well in the format host:instance.
None.