There's a klipsch 2.1 sub up for grabs on ebay right now. It's unclear whether it works at all, but assuming that it does, will I be able to adjust the volume on it? The plan is to use a splitter in tandem with the monsoon system I have now. Or do you think perhaps I could just use a single speaker from another set to control the volume? Thanks. Auction ends in 4ish hours.