Any RCA input is a low level only input, meaning it is only safe to send un-amplified source to this input. By using the speaker wires from the sub in a game you are using a high level (amplified) source. Usually these types of subs have both low and high Z inputs, and in this case this sub does. There are two sets of speaker wire terminals on the lower right of the amp. One is speaker output, one is input. You MUST use the speaker input if using an amplified source from your game or you will absolutely damage the amp/sub. (when that happens will depend on how loud you have the game and the settings you've got dialed in on the sub, and the duration of use)
For those of you that are using the RCA line levels for inputs directly from a games speaker, please reconfigure your setup before you damage your equipment.
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