Was going to say, done a few Google searches before I found S-Voice turns on when you double click the home button
Then I found the the reason the voice command did not work is the command is "Hi Galaxy", really this is not as stupid as it sounds the lock screen says swipe to up lock or say "Wake-Up" command..... so I am shouting at the stupid thing "WAKE UP", the command is "Hi Galaxy" like I should know.
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