subwoofer hum

  1. M

    Need some help with subwoofer thumping

    So I have a huge box for my 2 12 inch kickers on my backseat of my truck and occasionally I just unplug them to make extra room for passengers. It has always worked fine, but last time I put them back in and then they started thumping, not a hum or anything. I messed with the gain on the amp and...