Logitech z-5500 sub popping?

hey this weekend its my formal and my mate owns a huge shed in the industrial area for the after party ;) anyway i own a z-5500 speaker system and my subwoofer POPS at half volume ( no boost ) i have a feeling its my itunes equalizer because the bass on 32Hz is set to like allmost max is this why its popping? i want to crank it up along with my mates z5500 and dont want to kill it and get this pop noise.. i only just purchased it about 3 weeks ago. so is it my fault that its popping am i pushing to much bass into it or the subs ruined? thanks for any advice