This is another option if you want your subs to come on automatically:
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Plug your TV (or AVR as long as it will be on whenever you want the subs on) into the "Master" slot (top right) and plug the subs into the "Controlled by Master" slots (left side). Easy!
But most modern AVR's will let you turn up the sub at the AVR and turn it down at the sub (to maintain the same net volume). This will often solve the problem!
