Always self-deafen (#1491)

src/main/java/com/jagrosh/jmusicbot/commands/MusicCommand.java

@@ -86,6 +86,7 @@ public abstract class MusicCommand extends Command
                 try 
                 {
                     event.getGuild().getAudioManager().openAudioConnection(userState.getChannel());
+                    event.getGuild().getAudioManager().setSelfDeafened(true);
                 }
                 catch(PermissionException ex) 
                 {