They always use the high pass setting to mask the problem of the speaker, who knows, they've probably sold that to a customer and returned coz of the problem, then sold it to you. Dont wait things like this needs to be dealt ASAP, the longer you dont talk to them, the lesser chance for you to get a replacement speaker, ask for a replacement. Just tell them its a dud speaker, tell them as soon as its been all hooked up to your head unit, thats the first sound you heard from that speaker. And always accept a sealed box as its a sign that it has never been used. You can tell the difference if the box/speaker has been opened. Go now and get a replacement, talk to the manager. Good luck! Let us know the outcome.